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The first streak of dawn is the signal for lowering the boats, all pulling for the head- waters, where the whales are expected to be found. As soon as one is seen, the officer who first discovers it sets a “ waif” (a small flag) in his boat, and gives chase. Boats belonging to other vessels do not interfere, but go in search of other whales. When pursuing, great care is taken to keep behind, and a short distance from the animal, until it is driven to the extremity of the lagoon, or into shoal water; then the men in the nearest boats spring to their oars in the exciting race, and the animal, swimming so near the bottom, has its progress impeded, thereby giving its pursuers a decided advantage: although occasionally it will sud- denly change its course, or “dodge,” which frequently prolongs the chase for hours, disposed of. The quantity found in any one we are convinced that mussels have been found individual would not exceed a barrelful. in the maws of the California Grays; but as From the testimony of several whaling-men yet, from our own observations, we have not whom we regard as interested and careful ob- been able to establish the fact of what their servers, together with our own investigations, principal sustenance consists. MazineE MAMMALS. — 4. 26 MARINE MAMMALS OF THE NORTH-WESTERN COAST. the boats cutting through the water at their utmost speed. At other times, when the cub is young and weak, the movements of the mother are sympathetically It is rare that the dam will When within “darting distance” (sixteen suited to the necessities of her dependent offspring. forsake her young one, when molested. or eighteen feet), the boat-steerer darts the harpoons, and if the whale is struck As soon as the boat is fast, the officer goes into the head,* and watches a favorable it dashes about, lashing the water into foam, oftentimes staving the boats. opportunity to shoot a bomb-lance. Should this enter a vital part and explode, it kills instantly, but it is not often this good luck occurs; more frequently two or three bombs are shot, which paralyze the animal to some extent, when the boat is hauled near enough to use the hand-lance. After repeated thrusts, the whale becomes sluggish in its motions; then, going “close to,’ the hand-lance is set into its ‘life,’ which completes the capture. The animal rolls over on its side, with fins extended, and dies without a struggle. Sometimes it will circle around within a small compass, or take a zigzag course, heaving its head and flukes above the water, and will either roll over, ‘‘fin out,’ or die under water and sink to the bottom. Thus far we have spoken principally of the females, as they are femnd.in, the lagoons. Mention has been made, however, of that general habit, common to both male and female, of keeping near the shore in making the passage between their northern and southern feeding-grounds. This fact becoming known, and the bomb- guny coming into use, the mode of capture along the outer coast was changed. The whaling parties first stationed themselves in their boats at the most favorable points, where the thickest beds of kelp were found, and there lay in wait watching for a good chance to shoot the whales as they passed. This was called ‘kelp whaling.” The first year or two that this pursuit was practiced, many of the animals * Whalemen call the forward part of a whale- boat the head, differing from merchantmen, who term it the bow; still, the oar next to the for- ward one in a whale-boat is named the bow- oar. And, likewise, when the boat is hauled close up to the whale by heaving the line out of the ‘“‘bow-chocks,” and taking it to one side against a cleat which is placed a few feet aft of the extreme bow, it is called ‘‘bowing- on.” ¢ The bomb-gun is made of iron, stock and all. It is three feet long, the barrel of which is twenty-three inches in length; diameter of bore, one and one-eighth of an inch; weight, twenty-four pounds. It shoots a bomb-lance twenty-one and a half inches long, and of a size to fit the bore. It is pointed at the end, with sharpened edges, in order to cut its way through the fibrous fat and flesh, and is guided by three elastic feathers, which are attached along the fuse tube, folding around it when in the barrel. The gun is fired from the shoulder, in the same way as a musket. For illustration, see plate xxiii. THE CALIFORNIA GRAY WHALE. 27 passed through or along the edge of the kelp, where the gunners chose their own distance for a shot. This method, however, soon excited the suspicions of these sagacious creatures. At first, the ordinary whale-boat was used, but the keen- eyed ‘‘Devil-fish” soon found what would be the consequence of getting too near the long, dark-looking object, as it lay nearly motionless, only rising and falling with one man to scull and another with the rolling swell. A very small boat to shoot—was then used, instead of the whale-boat. This proved successful for a time, but, after a few successive seasons, the animals passed farther seaward, and at the present time the boats usually anchor outside the kelp. The mottled fish being scen approaching far enough off for the experienced gunner to judge nearly where the animal will ‘break water,” the boat is sculled to that place, to await the ba “rising.” If the whale ‘‘shows a good chance,” it is frequently killed instantly, and sinks to the bottom, or receives its death-wound by the bursting of the bomb- lance. Consequently, the stationary position or slow movement of the animal enables the whaler to get a harpoon into it before sinking. To the harpoon a lne is attached, with a buoy, which indicates the place where the dead creature lies, should it go to the bottom. Then, in the course of twenty-four hours, or in less time, it rises to the surface, and is towed to the shore, the blubber taken off and tried out in pots set for that purpose upon the beach. Another mode of capture is by ships cruising off the land and sending their boats inshore toward the line of kelp; and, as the whales work to the southward, the boats, being provided with extra large sails, the whalemen take advantage of the strong northerly winds, and, running before the breeze, sail near enough to be able to dart the hand-harpoon into the fish. ‘Getting fast” in this way, it is killed in deep water, and, if inclined to sink, it can be held up by the boats till the ship comes up, when a large “fluke-rope” is made fast, or the “fin-chain” is secured to one fin, the ‘‘cutting-tackle” hooked, and the whale “cut in” immedi- ately. This mode is called ‘‘sailing them down.” Still another way of catching them is with ‘“Greener’s Harpoon Gun,” which is similar to a small swivel-gun. It is of one and a half inch bore, three feet long in the barrel, and, when stocked, weighs seventy-five pounds. The harpoon, four feet and a half long, is projected with considerable accuracy to any distance under eighty-four yards. The gun is mounted on the bow of the boat. A variety of manceuvres are practiced when using the weapon: at times the boat lying at anchor, and, again, drifting about for a chance-shot. When the animal is judged to be ten fathoms off, the gun is pointed eighteen inches below the back; if fifteen fathoms, eight or ten inches below; if eighteen or twenty fathoms distant, the gun is sighted at the top of its back. 28 MARINE MAMMALS OF THE NORTH-WESTERN COAST. Still another strategic plan has been practiced with successful results, called ‘whaling along the breakers.” Mention has been already made of the habit which these whales have of playing about the breakers at the mouths of the lagoons. This, the watchful eye of the whaler was quick to see, could be turned to his advantage. After years of pursuit by waylaying them around the beds of kelp, the wary animals learned to shun these fatal regions, making a wide deviation in their course to enjoy their sports among the rollers at the lagoons’ mouths, as they passed them either way. But the civilized whaler anchors his boats as near the roaring surf as safety will permit, and the unwary ‘‘Mussel-digger” that comes in reach of the deadly harpoon, or bomb-lance, is sure to pay the penalty with its life. If it come within darting distance, it is harpooned; and, as the stricken animal makes for the open sea, it is soon in deep water, where the pursuer makes his capture with comparative ease; or if passing within range of the bomb-gun, one of the explosive missiles is planted in its side, which so paralyzes the whale that the fresh boat’s-crew, who have been resting at anchor, taking to their oars, soon overtake and dispatch it. The casualties from coast and kelp whaling are nothing to be compared with the accidents that have been experienced by those engaged in taking the females in the lagoons. Hardly a day passes but there is upsetting or staving of boats, the crews receiving bruises, cuts, and, in many instances, having limbs broken; and repeated accidents have happened in which men have been instantly killed, or received mortal injury. The reasons of the increased dangers are these: the quick and deviating movements of the animal, its unusual sagacity, and the fact of the sandy bottom being continually stirred by the strong currents, making it difficult to see an object at any considerable depth. When a whale is “struck” at sea, there is generally but httle difficulty in keeping clear. When first irritated by the har- poon, it attempts to escape by “running,” or descending to the depths below, taking out more or less line, the direction of which, and the movements of the boat, indicate the animal’s whereabouts. But in a lagoon, the object of pursuit is in narrow passages, where frequently there is a swift tide, and the turbid water pre- vents the whaler from seeing far beneath the boat. Should the chase be made with the current, the fugitive sometimes stops suddenly, and the speed of the boat, together with the influence of the running water, shoots it upon the worried animal when it is dashing its flukes in every direction. The whales that are chased have with them their young cubs, and the mother, in her efforts to avoid the pursuit of herself and offspring, may momentarily lose sight of her little one. Instantly she oe, Wah ee “HONWO L'dIVIS 01 CHHIVILV F3N¥T 9 4SVLS 01 GHHOVTAWY NOOAMWHG AGO H‘NOOAIVH TO MAIN TOGTE TINVI JO MaIA TOCT CMV TOS'2 CIHOVLLV ANTI HLIM. (WH NOOTHVH | ‘SLNAWITIWT ONITVHM CNY SONV9 ONITVHM SNVIGNI LSAM HLYON JP DP UAUMMEIO YW} HS Fa 8 UO YET f ( UG CM Hi rN AD 181g THE CALIFORNIA GRAY WHALE. 29 will stop and ‘‘sweep”’ around in search, and if the boat~comes in contact with her, it is quite sure to be staved. Another danger is, that in darting the lance at the mother, the young one, in its gambols, will get in the way of the weapon, and receive the wound, instead of the intended victim. Sometimes the calf is fastened to instead of the cow. In such instances the mother may have been an old frequenter of the ground, and been before chased, and perhaps have suffered from a previous attack, so that she is far more difficult to capture, staving the boats and escaping after receiving repeated wounds. One instance occurred in Magdalena Lagoon, in 1857, where, after several boats had been staved, they being near the beach, the men in those remaining afloat managed to pick up their swimming comrades, and, in the meantime, to run the line to the shore, hauling the calf into as shallow water as would float the dam, she keeping near her troubled young one, giving the gunner a good chance for a shot with his bomb-gun from the beach. A similar instance occurred in Scammon’s Lagoon, in 1859. The testimony of many whaling-masters furnishes abundant proof that these whales are possessed of unusual sagacity. Numerous contests with them have proved that, after the loss of their cherished offspring, the enraged animals have given chase to the boats, which only found security by escaping to shoal water or to shore. After evading the civilized whaler and his instruments of destruction, and per- haps while they are suffering from wounds received in their southern haunts, these migratory animals begin their northern journey. The mother, with her young grown to half the size of maturity, but wanting in strength, makes the best of her way along the shores, avoiding the rough sea by passing between or near the rocks and islets that stud the points and capes. But scarcely have the poor creatures quitted their southern homes before they are surprised by the Indians about the Strait of Juan de Fuca, Vancouver and Queen Charlotte’s Islands. Like enemies in ambush, these glide in canoes from island, bluff, or bay, rushing upon their prey with whoop and yell, launching their instruments of torture, and like hounds worry- ing the last life-blood from their vitals. The capture having been effected, trains of canoes tow the prize to shore in triumph. The whalemen among the Indians of the North-west Coast are those who delight in the height of adventure, and who are ambitious of acquiring the greatest reputation among their fellows. Those among them who could boast of killing a whale, formerly had the most exalted mark of 30 MARINE MAMMALS OF THE NORTH-WESTERN COAST. honor conferred upon them by a cut across the nose; but this custom is no longer observed. The Indian whaling-canoe is thirty-five feet in length. Hight men make the crew, each wielding a paddle five and a half feet long. The whaling-gear consists of harpoons, lines, lances, and seal-skin buoys, all of their own workmanship. The cutting material of both lance and spear was formerly the thick part of a mussel- ? shell, or of the ‘“‘abelone ;” the line made from cedar withes, twisted into a three- strand rope. The buoys are fancifully painted, but those belonging to each boat have a distinguishing mark. The lance-pole, or harpoon-staff, made of the heavy wood of the yew-tree, is eighteen feet long, weighing as many pounds, and with the lance attached is truly a formidable weapon. Their whaling-grounds are limited, as the Indians rarely venture seaward far out of sight of the smoke from their cabins by day, or beyond view of their bon- fires at night. The number of canoes engaged in one of these expeditions is from two to five, the crews being taken from among the chosen men of the tribe, who, with silent stroke, can paddle the symmetrical canim close to the rippling water beside the animal; the bowman then, with sure aim, thrusts the harpoon into it, and heaves the line and buoys clear of the canoe. The worried creature may dive deeply, but very little time elapses before the inflated seal-skins are visible again. The instant these are seen, a buoy is elevated on a pole from the nearest canoe, by way of signal; then all dash, with shout and grunt, toward the object of pur- suit. Now the chase attains the highest pitch of excitement, for each boat being provided with implements alike, in order to entitle it to a full share of the prize its crew must lodge their harpoon in the animal, with buoys attached; so that, after the first attack is made, the strife that ensues to be next to throw the spear creates a scene of brawl and agility peculiar to these savage adventurers. At length the victim, becoming weakened by loss of blood, yields to a system of torture characteristic of its eager pursuers, and eventually, spouting its last blood from a lacerated heart, it writhes in convulsions and expires. Then the whole fleet of canoes assists in towing it to the shore, where a division is made, and all the inhabitants of the village greedily feed upon the fat and flesh till their appetites are satisfied. After the feast, what oil may be extracted from the remains is put into skins or bladders, and is an article of traffic with neighboring tribes or the white traders who occasionally visit them. These “whales of passage,” when arrived in the Arctic Ocean and Okhotsk Sea, are seen emerging between the scattered floes, and even forcing themselves through the field of ice, rising midway above the surface, and blowing in the same THE CALIFORNIA GRAY WHALE. 31 attitude in which they are frequently seen in the southern lagoons; at such times the combined sound of their respirations can be heard, in a calm day, for miles across the ice and water. But in those far northern regions, the animals are rarely pursued by the whale-ship’s boats: hence they rest in some degree of security; yet even there, the watchful Esquimaux steal upon them, and to their primitive weapons and rude processes the whale at last succumbs, and supplies food and substance for its captors. The Esquimaux whaling-boat, although to all appearance simple in its con- struction, will be found, after careful investigation, to be admirably adapted to the purpose, as well as for all other uses necessity demands. It is not only used to accomplish the more important undertaking, but in it they hunt the walrus, shoot game, and make their long summer-voyages about the coast, up the deep bays and long rivers, where they traffic with the interior tribes. When prepared for whaling, the boat is cleared of all passengers and useless incumbrances, nothing being allowed but the whaling-gear. Hight picked men make the crew.* Their boats are twenty-five to thirty feet long, and are flat on the bottom, with flaring sides and tapering ends. The framework is of wood, lashed together with the fibres of baleen and thongs of walrus-hide, the latter article being the covering, or plank- ing, to the boat. The implements are one or more harpoons, made of ivory, with a point of slate-stone or iron; a boat-mast, that serves the triple purpose of spreading the sail and furnishing the staff for the harpoon and lance; a large knife, and eight paddles. The knife lashed to the mast constitutes the lance. The boat being in readiness, the chase begins. As soon as the whale is seen and its course ascertained, all get behind it: not a word is spoken, nor will they take notice of a passing ship or boat, when once excited in the chase. All is silent and motionless until the spout is seen, when they instantly paddle toward it. The spouting over, every paddle is raised; again the spout is seen or heard through the fog, and again they spring to their paddles. In this manner the animal is approached near enough to throw the harpoon, when all shout at the top of their voices. This is said to have the effect of checking the animal’s way through the water, thus giving an opportunity to plant the spear in its body, with line and buoys attached. The chase continues in this wise until a number of weapons are firmly fixed, causing the animal much effort to get under water, and still more to remain down; so it soon rises again, and is attacked with renewed vigor. It is the *It is said by Captain Norton, who com- several years ago, that the women engage in the manded the ship Citizen, wrecked in the Arctic chase. bo MARINE MAMMALS OF THE NORTH-WESTERN COAST. oo established custom with these simple natives, that the man who first effectually throws his harpoon, takes command of the whole party: accordingly, as soon as the animal becomes much exhausted, his baidarra is paddled near, and with surprising quickness he cuts a hole in its side sufficiently large to admit the knife and mast to which it is attached; then follows a course of cutting and piercing till death ensues, after which the treasure is towed to the beach in front of their huts, where it is divided, each member of the party receiving two ‘‘slabs of bone,” and a like proportion of the blubber and entrails; the owners of the canoes claiming what remains. The choice pieces for a dainty repast, with them, are the flukes, lips, and fins. The oil is a great article of trade with the interior tribes of ‘‘reindeer-men:” it is sold in skins of fifteen gallons each, a skin of oil being the price of a reindeer. The entrails are made into a kind of souse, by pickling them in a liquid extracted from a root that imparts an acrid taste: this preparation is a savory dish, as well as a preventive of the scurvy. The lean flesh supplies food for their dogs, the whole troop of the village gathering abot the carcass, fighting, feasting, and howl- ing, as only sledge-dogs can. Many of the marked habits of the California Gray are widely different from those of any other species of balena. It makes regular migrations from the hot southern latitudes to beyond the Arctic Circle; and in its passages between the extremes of climate it follows the general trend of an irregular coast so near that it is exposed to attack from the savage tribes inhabiting the sea-shores, who pass much of their time in the canoe, and consider the capture of this singular wanderer a feat worthy of the highest distinction. As it approaches the waters of the torrid zone, it presents an opportunity to the civilized whalemen—at sea, along the shore, and in the lagoons—to practice their different modes of strategy, thus hastening the time of its entire annihilation. This species of whale manifests the greatest affection for its young, and seeks the sheltered estuaries lying under a tropical sun, as if to warm its offspring into activity and promote comfort, until grown to the size Nature demands for its first northern visit. When the parent animals are attacked, they show a power of resistance and tenacity of life that distinguish them from all other Cetaceans. Many an expert whaleman has suffered in his encounters with them, and many a one has paid the penalty with his life. Once captured, however, this whale yields the coveted reward to its enemies, furnishing sustenance for the Hsquimaux whaler, from such parts as are of little value to others. The oil extracted from its fatty covering is exchanged with remote tribes for their fur- clad animals, of which the flesh affords the venders a feast of the choicest food, Plate V. ur Auth Britton + Aer 8, el CAMPO. S TAL, ris CALIFORNIA GRAYS AMONG THE lc a THE CALIFORNIA GRAY WHALE. 33 and the skins form an indispensable article of clothing. The North-west Indians realize the same comparative benefit from the captured animals as do the Hsqui- maux, and look forward to its periodical passage through their circumscribed fishing- grounds as a season of exploits and profit. The civilized whaler seeks the hunted animal farther seaward, as from year to year it learns to shun the fatal shore. None of the species are so constantly and variously pursued as the one we have endeavored to describe; and the large bays and lagoons, where these animals once congregated, brought forth and nurtured their young, are already nearly deserted. The mammoth bones of the California Gray lie bleaching on the shores of those silvery waters, and are scattered along the broken coasts, from Siberia to the Gulf of California; and ere long it may be questioned whether this mammal will not be numbered among the extinct species of the Pacific. MARINE MAMMALS.—5. CYLAPTER: i, THE FINBACK WHALE. BaLEnorrera VELIFERA, Cope. (Plate u, fig. 2.) Another species of the whale tribe is known as the Finback, or Finner, whose geographical distribution is as extended as that of the Sulphurbottom, and which ranks next to it in point of swiftness. One picked up by Captain Poole, of the bark Sarah Warren, of San Francisco, affords us the following memoranda: Length, sixty-five feet; thickness of blubber, seven to nine inches; yield of oil, seventy-five barrels; color of blubber, a clear white. Top of head quite as flat and straight as that of the Humpback. Baleen, the longest, two feet four inches; greatest width, thirteen inches; its color, a light lead, streaked with black, and its surface presents a ridgy appearance crosswise ; length of fringe to bone, two to four inches, and in size this may be compared to a cambric needle. A Balenoptera, which came on shore near the outer heads of the Golden Gate, gave us the opportunity of obtaining the following rough measurements : Ft. In. Dsen ti sieraco ceca vie eis a uals ens vt fe i deena stag ate Botte nae ca terete Sat ceell aa 60 00 Hromenibsend=to: pectoralsiaciananun so sen oulnnan epee kota eed hans nee ae 15 00 Prom -nib=end. 10. cormen-of. Mm OWtlins Neue M sachs teers perenne eee ecient 12 00 ROM DUD SEN OO y. Cis sisson 8 eats tx ectiaee aictetuas oet ei er a sS eee ag ena vada cea, 12 06 From notch.ot-caudal into. Senital siti sn. arn natdaeaiee shh a oe ee bee 21 00 Hrom notch: or-canudal sinrto vent... 2 iio cae a acne pone Sneak ee eee eta 19 06 Hix pansion Of-caucal sfines 2. + csent count narcen ata ee asi mca abe amet TAO te 14 00 Its side fins and flukes are in like proportion to the body as in the California Gray. Its throat and breast are marked with deep creases, or folds, similar to the Humpback. Color of back and sides, black or blackish-brown (in some individ- uals a curved band of lighter shade marks its upper sides, between the spiracles and pectorals) ; belly, a milky white. Its back fin is placed nearer to the caudal than the hump on the Humpback, and in shape approaches to a right-angled [34] Dn | THE FINBACK WHALL. (She) triangle, but rounded on the forward edge, curved on the opposite one; the longest side joins the back in some examples, and in others the anterior edge is the longest. The gular folds spread on each side to the pectorals, and extended half the length of the body. The habitual movements of the Finback in several points are peculiar. When it respires, the vaporous breath passes quickly through its spiracles, and when a fresh supply of air is drawn into the breathing system, a sharp and somewhat musical sound may be heard at a considerable distance, which is quite distinguish- able from that of other whales of the same genus. (We have observed the interval between the respirations of a large Vinback to be about seven seconds.) It fre- quently gambols about vessels at sea, in mid-ocean as well as close in with the coast, darting under them, or shooting swiftly through the water on either side; at one moment upon the surface, belching forth its quick, ringing spout, and the next instant submerging itself bencath the waves, as if enjoying a spirited race with the ship dashing along under a press of sail. In beginning the descent, it assumes a variety of positions: sometimes rolling over nearly on its side, at other times rounding, or perhaps heaving, its flukes out, and assuming nearly a perpendicular attitude. Frequently it remains on the surface, making a regular course and several uniform ‘‘blows.” Occasionally they congregate in schools of fifteen to twenty, or less. In this situation we have usually observed them going quickly through the water, several spouting at the same instant. Their uncertain movements, however —often showing themselves twice or thrice, then disappearing—and their swiftness, make them very difficult to capture. The results of several attempts to catch them were as follows: from the ship one was shot with a bomb-gun, which did its work so effectually, that although the boat was in readiness for instant lowering, before it got within darting distance the animal, in its dying contortions, ran foul of the ship, giving her a shock that was very sensibly felt by all on board, and lkewise a momentary heel of about two streaks. We had a good view of the under-side of the whale as it made several successive rolls before disappearing, and our obser- vations agreed with those noted on board the Sarak Warren in relation to color and the creases on throat and breast. The under-side of the fins was white also. At another time the whale died about ten fathoms under water, and after carefully hauling it up in sight, the “iron drawed, and away the dead animal went to the depths beneath.” Frequently we have “lowered” for single ones that were playing about the ship, but by the time the boats were in the water nothing more would be seen of them, or, if seen, they would be a long way off, and then disappear. An instance occurred in Monterey Bay, in 1865, of five being captured under 36 MARINE MAMMALS OF THE NORTH-WESTERN COAST. the following circumstances: A ‘‘pod” of whales was seen in the offing, by the whalemen, from their shore station, who immediately embarked in their boats and gave chase. On coming up to them they were found to be Finbacks. One was harpooned, and, although it received a mortal wound, they all ‘run together” as before. One of the gunners, being an expert, managed to shoot the whole five, and they were all ultimately secured, yielding to the captors a merited prize. We have noticed large numbers of these whales along the coast during the summer months, and they seem to be more together at that particular season; but, as the opportunities for observing their habits have been much greater at that time of the year, we may have been led into error upon this particular point. Their food is of the same nature as that of the other rorquals, and the quantity of codfish which has been found in them is truly enormous. On the northern coast, the Finbacks, in many instances, have a much larger fin than those in warmer lati- tudes, and we are fully satisfied that these are a distinct species, confined to the northern waters. We have had but little opportunity to observe the Finbacks that frequently rove about the Gulf of Georgia and Fuca Strait. Several have been seen, however, in May and June, on the coasts of California and Oregon, and in Fuca Strait in June and July of the year 1864; these observations satisfy us that the dorsal fin of this—the northern species referred to—is strikingly larger than in the more southern Finbacks. Appended are the outlines of one individual of several seen in Queen Charlotte Sound, in February, 1865, which is a fair representation of them all. Those we have noticed about Fuca Strait seem to have the back fin modified in size between the extremely small one found on the coast of Lower California and the one here represented. “DONVT'9 ‘SAVIS OL GAHOVIIV NOOGUVH'S NOOdYVH JO MIA AUIS + ‘NOOdUVH 40 MAIA 3904 °e'AONA' 2° SONWI'L “SLNAWATdAT ONIIVHM. GNV'TONVO ONITVHM XNVWINdgsd 4 hay YUONIIg' YI] ‘Jap uowueo Wd LY TA 8teld t™~ om FINBACK WHALE. THE PuTLINES OF A NorTHERN PINBACK, CHAPTER. HI, THE WUMPBACK WHALE. MEGAPTERA VERSABILIS, Cope. (Plate vii, fig. 1.) The Humpback is one of the species of rorquals that roam through every ocean, generally preferring to feed and perform its uncouth gambols near extensive coasts, or about the shores of islands, in all latitudes between the equator and the frozen oceans, both north and south. It is irregular in its movements, seldom going a straight course for any considerable distance; at one time moving about in large numbers, scattered over the sea as far as the eye can discern from the mast-head ; at other times singly, seeming as much at home as if it were surrounded by hun- dreds of its kind; performing at will the varied actions of ‘breaching,’ ‘‘rolling,” “finning,”’ “lobtailing,’ or “scooping;” or, on a calm, sunny day, perhaps lying motionless on the molten-looking surface, as though life were extinct. Its shape, compared with the symmetrical forms of the Finback, California Gray, and Sulphurbottom, is decidedly ugly, as it has a short, thick body, and frequently a diminutive “small,” with inordinately large pectorals and flukes. <A protuberance, of variable shape and size in different individuals, placed on the back, about one-fourth the length from the caudal fin, is called the hump. An- other cartilaginous boss projects from a centre fold immediately beneath the anterior point of the under jaw, which, with the flukes, pectorals, and throat of the creature, are oftentimes hung with pendent parasites* (Otion Stimpsoni), and on *We print here Dall’s description of the unusually long and stout. First pair of hands Cyamus suffusus; also his remarks on the Ofion quadrant-shaped ; second pair slightly punctate, Stimpsoni (Proc. Cal. Acad. Sci., Dec. 18th, arcua‘e, emarginate on the inferior edge, with a pointed tubercle on each side of the emargina- tion. Third joint of the posterior lees keeled Cyamus suffusus, n. sp. Body flattened, elon- above, with a prong below. Pleon extremely gate; segments, sub-equal, outer edges widely minute. Segments smooth. No ventral spines separated. Branchie single, cylindrical slender, on posterior segments. Color, yellowish white, with a very short papilliform appendage before suffused with rose-purple, strongest upon the and behind each branchia. Superior antenne antenne and branchie. Length, 0.41 inches; [38] 1872). Illustrations, figures 3 and 5, plate x. THE HUMPBACK WHALE. 39 the males it is frequently studded with tubercles, as upon the head. A bulge also rounds down on the lower part of the ‘small,’ nearly midway between the hump and caudal. one. animal of abnormal proportions. Its under jaw extends forward considerably beyond the upper All these combined characteristics impress the observer with the idea of an The top of its head is dotted with irregular, rounded bunches, which rise about one inch above the surface, each covering nearly four square inches of space. The following measurements and memoranda of a male Humpback were taken by Captain I. §. Rediield, of the whaling and trading brig Manuella, while cruising in Behring Sea, September 17th, 1866: Mxtreme length ).....02 cones leet auke oe eas Length of pectoralg................ 0.0005 Breadth of pectorals...................00- Distance from snout to pectorals.......... Distance from corner of mouth to snout... Distance from eye to snout Distance from spout-holes to snout....... Expansion of flukes...................0005 Breadth of -tlulses a: 24S aeatscern ae eras Distance from anus to flukes.............. breadth (of body), 0.25 inches. All the speci- meus which have passed under my obscrvation, some eight or ten in number, were males. Habitat, on the Humpback Whale (degaptera versabilis, Cope) Monterey, California. Orton, Leach. Otion, Leach. ili, p. 170. Olion Slimpsoni, Dall, n. sp. Scuta only present, beaked, with the um- bones on the occludent margins; anterior pro- longation the longer, pointed, rather slender ; posterior prolongation, rounded, wider ; external margin concave; color (in spirits), hght orange, with a dark purple streak on the rostral surface and on each side of the peduncle; while the lateral surfaces of the body-case and lobes are mottled with dark purple. The lower lip of the orifice is transversely striated and translucent ; the upper margins slightly reflexed internally, white; in some specimens with two prolonga- tions or small lobes above, which are wanting Ency. Britannica, suppl. vol. Ft. In Een ttaist herent aio eh exe araeielosom europea. EO 30) UDiesena aio) tin tones caer Cet ansyer terse cunaterate? oct seys 13.7 ahapeharo igus Seeretarpionesauereuune Didyaaserne ate are cuales 3.2 Maal du ovay stadone ona nue auetaleGslevecaves aeeteraimeeten 6 12 0 Diya by a qatanshot Biers eka Disuaseies ioue/ennce Tonsre tates eee & 9 6 afer Sabana oteita "eueo.sel Sato: Gceceponetencievel stele vapererer eA 10 2 sxausivererer oicha@re/ wie) aceraiosnt en SiahelssrsTee lettLea 9 4 Sen aheuayatanavarentrn sotsre ay suouelete ialaratal Sons auareae 15 7 Sarena aay elpyatiateotat enarencme’ era lai etenatetoeenctste nt 3°04 widveduh es talstada oles laze’ auetareuansr eases anata. Shaueacnts 11 6 in other specimens. The tubular prolongations very irregular and variable in size and form, usually unsymmetrical; one sometimes nearly Length of peduncle, 2.08 inches; of body, 2.16 inches; of lobes, 2.00 inches; of ori- fice, 1.18 inch; of scuta, 0.55 inch; width of scuta, 0.16 inch. Habitat, on the Humpback (JL. versabilis) ; sessile on the Coronule which infest that spe- cies, but never, so far as I have observed, on the surface of the whale itself. Dr. Leach describes five calcareous species, having the scuta, terga, and rostrum of the typ- ical species (O. Cuvieri, Leach) and they are figured by Reeve; but this species has certainly only the scuta. Whether this difference is of more than specific value I am not able to de- cide, owing to the great paucity of works of reference here. I should be unwilling to de- scribe the species, were it not that it was sub- mitted to the late lamented Dr. Stimpson for examination, and was pronounced by him to be new. abortive. 40 MARINE MAMMALS OF THE NORTH-WESTERN COAST. Ft. In. Distance: itom~e eenital- slit: to “fukést: nn Yana tates, weeds aes ee cvenetea inechuneateatre tins 17 0 enethzob folds on belive sc 2 sissies otsaeesst, tach aun isa tetere wouaes aes Sue ecore. ob sas ane nue ieset tol Stes 16 0 Whole breadth of folds on belly...... 0. cece cece ee eee 10 0 Distance: from, flukes fo “Wurm p cies siacasossa eae w levee Soa ciane eeahe lee ae Gracy ehadlace. ca ane 12 3 Peneth- of hump, along the: backs. icscu5 sce ace edacets ceeds bene dees theta tet ecetuents sh aie any ates 3.0 Flere ht sof Wm pre aicacrie. esd stetrct ste lta skare case se yareye dseazavensusnsuaeset Scho nator cee Seucnycteeetemec ats 1 0 Depth of small close to flukes...... Boriseyrsahs ssuletau svavirahegie cents och one nomer seat tar essai 2 6 ‘Rhickmessof wsmallclose.:to ukesns 25 20 ciel cia ack erecta aus ced e.eetead cates 1 6 Thickness of blubber, five to ten inches; color of blubber, yellowish white ; yield of oil, forty barrels; number of folds on belly, twenty-six, averaging from four to six inches in width. These folds, which extend from the anterior portion of the throat over the belly, terminating a little behind the pectorals, are capable of great expansion and contraction, which enables the Humpbacks, as well as all other rorquals, to swell their maws when their food is in abundance about them. The following additional measurements, etc., were taken from Humpbacks capt- ured on the coast of Upper California, in 1872. 1. Sex, female. Color of body, black above, but more or less marbled with white below. Fins, black above, and dotted with white beneath. Color of blub- ber, white. Number of folds on throat and breast, twenty-one, the widest of which were six inches. Yield of oil, thirty-five barrels. The yield of bone, which is of inferior quality, is about four hundred pounds to a hundred barrels of oil. Ft. In, Ft. In Mength: of animal. o..34 oo5 cae eee ia: 48 0 Anus to notch of caudal fin............ 12 6 Length of each pectoral................ 13 0 Genital slit to notch of caudal fin...... 12 11 Thickness of each pectoral.............. 0 8 Length of genital slit.................. 3 6 Breadth of each pectoral............... 3.5 Size uround the body behind pectorals.. 25 0 Expansion of caudal fin, or flukes...... 18 0 Average thickness of blubber........... 0 5 Breadth of each lobe................... 36 Depth of small at junction with caudal fin, 1 9 Thickness of each lobe................. 0 9 Thickness of small at junction with caud- From nib-end to pectorals............. 16 0 SULSSHI g Leche eee tela Ce 1 6 Pectorals to top of back............... 4 6 From nib-end to hump................ 28 0 Corner of mouth to nib-end........... 10 0 Heightuok hump usc acento ere 0 10 Corner of mouth to top of head........ 5 4 Mento th:of hum pases weston scree 4 0 Hye*< 0 “Mik s€ndst een civaraadercecees 10 10 Thickness of black skin................ 0 of Hye to top of head.................... de Oi Wier boMeanas ayes Ga hiatds selena e ters o 2 0 Spiracles to nib-end................... 8 0 Dength: of “ear Slits. conden on auceesaneens 0 14 Length of exterior opening of spiracles... 1 6 Navel to genital slit...........0....0... 5 0 The nib-end, or point of the upper jaw, fell short of the extremity of the *We refer the reader to fig. 4, plate x, for forty-six feet in length. The figure is drawn illustration of an eye taken from a Humpback to natural size. Ss Ni i _Scammon 1. HUMPBACK ( MEGAPTERA VERSABILIS COPE.) 9 vs SHA ED FINNER ({BALAZNOPTERA DAVIDSONI, Scammon) THE HUMPBACK WHALE. 4] lower one about fifteen inches. The tongue and throat were of a leaden color, The orbit of the eye was four inches in diameter. The longest plate of bone, or baleen, was two feet; its color, black, with a fringe of lighter shade. 2. Sex, female. Color of body, black, with slight marks of white beneath. Color of pectorals, black above, white below. Color of flukes, black above and below. Color of blubber, white; average thickness of same, six inches. Yield of oil, thirty barrels. Gular folds, eighteen. Tubercles on lips, nine. Ft. In. Ft. In. Bength of animalcecwciecae cuvenaiees 48 0 From nib-end to pectorals............. 16 6 Length of pectorals: 2.0.06 5008 oes esas 13 0 Notch of flukes to anus................ 11 6 Breadth of pectorals................... 3 0 Notch of flukes to genital slit.......... 12 0 Thickness of pectorals.................. 0 8 Length of longest baleen.............. 2 9 Expansion of flukes.................... 14 0 Breadth of longest baleen.............. 0 10 Breadth: of: Nukes: oi. aces a eb ae Sees 4 3 3. Sex, female. Color of body, black above, slightly mottled with white and gray below. Fins and flukes, black above, white beneath. Color of blubber, white ; thickness of same, six to nine inches. Yield of oil, forty barrels. Number of laminze, five hundred and forty; black, streaked with white, or hght lead color. Ft. In. Ft. In.
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Peroneal M Ext. Long. Hallucius Tibialis Anticus Ant. Tibial Abv. Bet. 11-12. Ant. Tibial 734 SPECIAL PHYSIOLOGY In the compilation of the above table it was found that the state- ments of Gray, Quain, and other anatomists do not agree as to the function of particular muscles. In all such cases the author has accepted the authority of Duchenne, whose classic work, "Physiologic des Mouvements," still remains without an equal. 3. Animal Mechanics. — Animal mechanics is the application of the laws of mechanics to animal motion. The bones are used as levers; the articular surfaces of bones usually serve as fulcrums, while the power is exerted by the muscles. In a vast majority of cases the bones represent levers of the third class — in which rapidity of motion is attained at the expense of power. In other words, the arrangement of the bone-muscle organs is such that a contraction of a muscle — moderate in extent and rate of motion — is manifested by a movement of the limb which is much in excess, as to extent and rate, of the movement of the power. In solving problems in animal mechanics the principal factors to be considered are: (i) the relative length of the two lever arms; (n) the relative size of the muscles involved in any movement; (in) the direction in which the power acts, and (iv) the weight to be moved. (a) Problems in Animal Mechanics. — Two typical problems in animal mechanics are the following:1 1. Determine, in a particular case, the tension exerted upon the tendo Achillis in supporting the weight (60 kilograms) of the subject upon the ball of the foot. 2. How much tension would there be on the biceps tendon in the subject upon your dissecting table when he holds a ten-kilo, iron ball in the most advantageous position? This is a typical problem, and its solution will make the difficulties to be encountered apparent. It will also show that nothing more than an approximate solution can be attained without an extended and detailed study. SOLUTION. — The principal muscle involved in the required action being the biceps, the most advantageous position is the one in which that muscle exerts its power in a line perpendicular to the lever. Placing the subject's arm as nearly as possible in that position, one takes the following measurements: (i) The long arm of the lever; this would be from the centre of articulation between the humerus and the ulna, to the centre of the ten-kilo, ball, which would be, approximately, to the distal extremities of the metacarpal bone (36 cm.), (n) The short arm of the biceps lever; this would be the 1 Both of the problems stated above are problems in " muscle statics." Such problems deal with tension upon muscles when the limb is in a certain fixed position. There are much more complicated problems which deal with the energy exerted in a more or less complex movement when the leverages and angles of tension are constantly varying. Such problems in "muscle dynamics" can only be solved by the application of higher mathematics. Otto Fischer, of Leipzig, has done much to throw light upon this field of physiology. See his "Beitrage zur Muskel-statik ;" also "Beitrage zu einer Muskel-dynamik." THE PHYSIOLOGY OF THE MUSCULAR SYSTEM 735 distance from the centre of the insertion of the biceps to the fulcrum — the centre of articulation (6 cm.), (in) The short arm of the lever for the brachialis anticus. If the brachialis anticus were exactly parallel to the biceps the short arm would be the distance from the insertion to the fulcrum (5 cm.), as in the biceps; but it is not parallel. A line drawn from the fulcrum perpendicular to the axis of the brachialis anticus, fa', is shorter than the line / a. The angle between the brachialis anticus and the biceps is approximately 10 degrees; therefore, the angle a f af would be approximately 10 degrees; then a' f is the cosine 10 degrees or 98 per cent, of the radius a / (5 cm.), or 4.9 cm. (iv) The power-arm of the supinator longus is the perpendicular distance from the fulcrum to the line of force of the supinator longus FIG. 295 Mechanics of flexion of the forearm. [The upper a is to be understood as a'.] and is represented by the line / s, which is 4.8 cm. Now the carpal and digital flexors which take origin from the huinerus act as forearm flexors after having flexed the carpus and digits. In the action under consideration they would not be brought into forcible action as carpal and digital flexors. We may, therefore, ignore them and confine our discussion to the three muscles mentioned above. In the action of the biceps the long arm is 36 cm. and the short arm 6 cm.; in the action of the brachialis anticus the long arm is 36 cm. and the short arm 4.9 cm.; in the action of the supinator longus the long arm is 36 cm. and the short arm 4.8 cm. Reducing these to per cent, ratios we have : For the biceps, which we will designate as 6, 16.6 per cent, leverage; for the brachialis anticus, which we will designate as a, 13.6 per cent, leverage; and for the 736 SPECIAL PHYSIOLOGY supinator longus, which we will designate as s, 13.3 per cent, leverage. But there is another important consideration: Fick has demon- strated that when the fibres are parallel the strength of two muscles is proportional to the areas of their cross-sections.1 The average ratio of the diameter of the three muscles in question is 4 : 2 : 1, respect- ively; but the areas of the cross-sections would be proportional to the squares of the diameters, or as 16 : 4 : 1, respectively. This means that with the same leverage the biceps would lift four times as much as the brachialis anticus, and that the brachialis anticus would, with the same leverage, lift four times as much as the supinator longus. We have now discussed the relation of these three factors as to leverage and as to relative power exerted. As to leverage one may say: The power of the three muscles varies in proportion to biceps leverage (bl) ; brachialis anticus leverage (a/); supinator longus leverage (si), respectively; or, mathematically expressed, P varies as bl : al : si, or varies as 16.6 : 13.6 : 13.3. As to cross-section one may say: The power varies in proportion to the respective cross-sections (s) or P varies as bs : as : ss = 16 : 4 : 1. Now, when any function varies with two or more variable factors, its variation when influenced by the action of all of these factors at once would be represented by the product of the several variables. Then the power varies as the leverage times the cross-section of each of the muscles when all act together, or, expressed mathematically, P varies as b(lXs): a(lXs): s(lXs). But b(lXs) = -- 16.6 X 16 = 265.6, or 79.7 per cent, of the total power exerted; a(lXs) = 13.6 X 4 = 54.4, or 16.3 per cent, of the total power exerted; s(lXs) = 13.3 X 1 = 13.3, or 4.0 percent, of the total power exerted; total = 333.3, or 100.0 per cent. But the weight supported by the action of these muscles is 10 kilos. If the biceps does 79.7 per cent, of the total work, it would support 7.97 kilos'. What would be tension upon the tendon of the biceps when it is supporting 7.97 kilos, at the end of its lever? One needs only to use the 16.6 per cent, leverage (7.97 -r- 16.6 per cent.) to find that the tension would be 47.8 kilos. A similar process shows that the approximate tension upon the tendon of the brachialis anticus is 12 kilos, and upon the tendon of the supinator longus 3 kilos. (b) The Amount of Contraction of a Muscle bears a fairly constant ratio to the resting length of the muscle. This law of muscle physiology was discovered and demonstrated by Ed. Fr. Weber2 and was cited by Strasser3 as an example of the adaptation of muscle tissue to the mechanical requirements of the body. Weber 1 Hermann's Handbuch der Physiologie, vol. i. p. 295. 2 Mechanik der menschlichen Gehwerkzeuge, 1851, s Funktionellen Anpassung der Quergestreiften Muskeln, 1883. THE PHYSIOLOGY OF THE MUSCULAR SYSTEM 737 showed that the maximum contraction of which a muscle fibre is capable is approximately 47 per cent, of its resting length. Both Weber and Strasser looked upon this as the factor which determines the length of the muscles, and the location of their points of origin and insertion. In all of the skeletal muscles the tension of the con- tracting muscle is greater than the weight lifted. The farther the insertion of a muscle from a joint (fulcrum) the less the tension upon the muscle and the greater the amount of contraction or shortening necessary; but the inherent structure of striated muscle tissue seems to set 47 per cent, as the limit of the extent of its contraction. The fact that all skeletal muscles actually do contract that much (varying however, in special instances from 44 per cent, to 62 per cent.) indicates that the position of the origin and insertion or the length of muscle tissue (excluding tendon) between the origin and insertion; or, more likely, that both of these structural features have been deter- mined by the laws of selection, and now represent in all highly organized animals the most perfect mechanical adjustment consistent with the inherent properties of muscle tissue. (c) Problems in Human Locomotion, (a) THE MUSCLES USED IN LOCOMOTION. — Let a person stand erect with heels together; let him take several steps forward and stop in a position similar to the one which he had at the beginning. What is the mechanism of starting? What muscles are involved in starting? What is the mechanism of locomotion? What muscles are involved in locomotion? What is the mechanism of equilibration while walking? What muscles are involved in maintaining the equilibrium while walking? What is the mechanism of stopping? What muscles are involved in stopping? How is the equilibrium maintained during the process of stopping? What muscles are involved in the maintenance of equi- librium while standing? How does running differ from walking in the starting, the locomotion, the equilibration, and the stopping? (ft) THE ENERGY INVOLVED IN LOCOMOTION. — How far is the body lifted at each step when one walks over a level surface? When one walks up an incline of 30 degrees? When one walks down an incline of 30 degrees? Does one do work while walking down hill? If so, how may it be computed ? If not, why does one become fatigued in descending an incline? How much energy will a 70-kilo. man expend in walking 1 kilo, on a level road ? (Suppose the man to be 172 cm. in height, and to have a pubic height of 88 cm.) A part of the energy will be expended (i) in lifting the body, (11) a part in maintaining equilibrium, (in) and a part in overcoming resistance. Express in kilogram-metres the amount of energy expended in (i). How could one determine the amount of energy expended in (11)? 47 DIVISION C. CHAPTEE XIII. REPRODUCTION.! THE PHYSIOLOGY AND MORPHOLOGY OF REPRODUCTION. 1. THE OVUM. 2. MATURATION. 3. FERTILIZATION. 4. SEGMENTATION. 5. THE EMBRYO: HISTOGENESIS. (a) THE DEVELOPMENT OF THE GERM LAYERS. (6) THE DEVELOPMENT OF THE PRIMITIVE SEGMENTS. (c) THE BEGINNING OF THE NERVOUS SYSTEM. (d) THE MESENCHYME. (e) THE ORIGIN OF THE URINARY SYSTEM. (/) SUMMARY OF EARLY DEVELOPMENT: HISTOGENESIS. 6. THE FETUS: ORGANOGENESIS. (a) THE CIRCULATORY SYSTEM. (6) THE RESPIRATORY SYSTEM. (c) THE DIGESTIVE SYSTEM. (d) THE UROGENITAL SYSTEM. (e) THE CENTRAL NERVOUS SYSTEM. 7. THE FETAL ENVELOPES. (a) THE FETAL MEMBRANES. (6) MATERNAL PORTION OF ENVELOPES: DECIDU^E AND PLACENTA. 8. THE PHYSIOLOGY OF THE EMBRYO AND FCETUS. (a) NUTRITION. (6) MOTOSENSORY ACTIVITY. 9. THE PHYSIOLOGY OF MATERNITY. (a) PREGNANCY AND PARTURITION. (6) LACTATION. THE parental phases of reproduction include all of those activities involved in the production of offspring. Two general phases in the production of offspring are (i) the transmission of hereditary char- 1 The introduction to the processes of reproduction may be found in Part I., Cellular Biology. It is proposed to give here a very brief summary of mammalian reproduction and development, especially emphasizing the physiologic phases of the processes. REPRODUCTION 739 acters and (n) the nourishment and protection of the young during a longer or snorter period of development. In mammalian reproduction one may profitably consider the following special processes: (i) The formation of the germ cells; the maturation of the germ cells; the conjugation or fusion of the germ cells (fertilization}, (n) The segmentation of the fertilized ovum; the intrauterine development successively, of the blastoderm, the gastrula, the three-layered embryo, and the foetus; parturition; lactation; extrauterine development. Some of these processes represent activities of the parents; some, those of the developing young. Human spermatozoa. X 1000. 1, in profile ; 2, viewed on the flat ; 6, head ; c, middle piece ; d, tail ; e, end piece of the tail, which is de- scribed as a distinct part by Retzius. (Schiifer, after Retzius.) Semidiagrammatic representation of a mammalian ovum. (Highly magnified.) sp, zona pellucida ; vi, vitellus ; gv, germinal vesicle ; gs, germinal spot. (Schiifer.) The paternal portion of the general process consists in the pro- duction of the male germ cells and assisting in the nourishment and protection of the young during its extrauterine development. The male reproductive cell — the spermatozoon (Fig. 296) — serves the double purpose (i) of transmitting to the offspring the hereditary characters of the paternal ancestral line, and (n) of inducing in the ovum the process of segmentation. The maternal portion of the general process consists in the pro- duction of the female germ cells and the protection and nourishment of the young during intrauterine development and infancy, and assisting in its nourishment and protection during childhood and youth. The offspring is passive as an individual during intrauterine life, 740 SPECIAL PHYSIOLOGY but its cells and tissues are exceedingly active. The activity takes the form of the following processes: Segmentation, formation of embryonic layers, development of tissues and organs drawing suste- nance for these structures from the maternal organism. Without further following the distinction between parental and embryonic processes we may now summarize the whole process of reproduction and development. 1. THE OVUM. The ovum is a simple, single cell. The parts of this gigantic cell have received special names: the cell wall is called the vitelline membrane; the protoplasm with its reserve nutriment is called the yolk, the nucleus, becomes the germinal vesicle; the nucleolus the germinal dot (Fig. 297). 2. MATURATION. Before the egg is ready to be fertilized the process of maturation takes place in the following manner, in the egg of an echinoderm (Fig. 298, a to g) : (i) The germinative vesicle gradually moves from the centre of the egg toward its surface, its nuclear membrane disappears, and the germinative dot breaks up into small, hardly visible fragments. (n) There arises out of a part of the nuclear substance of the germinative vesicle a nuclear spindle which pursues still farther the direction taken by the germinative vesicle until it touches with its apex the surface of the yolk, where it assumes a position with its long axis in the direction of a radius of the sphere. (in) A genuine process of cell division soon takes place here, which is to be distinguished from the ordinary cell division only in this: that the two products of cell division are of very unequal size. More exactly expressed, this process is a cell-budding (gemmation). This process of gemmation occurs twice. The two small cells are called polar bodies. (iv) After the conclusion of the second process of budding the remaining part of the spindle, one-fourth of the original spindle, is left in the cortical layer of the yolk. From this arises a new, small, vesicular nucleus, which consists of a homogeneous fluid substance without distinct nucleolus. From its peripheral position it usually migrates slowly back toward the middle of the egg. Thus it completes in four phases the process of maturation. There is no reason to doubt that the process of maturation in the mammalian egg is in any important feature different from that in the egg of the echinoderm. REFR OD UCTION 741 3. FERTILIZATION. FERTILIZATION is the union of egg cell and spermatic cell, more technically union of their nuclei; without this union a complete, I p * £ 5^ "S c a 60 £ s>c ~s :* S « * "3 •e 9 g^ 5 ^ /X:> • Jt~*~ • •'••• v -~ • iifej-^ =i ft"/ - - v^-r ^ ^_ ^ fHii-^' iv ;:'--';. . - Va>" V. vx/isw^-!- I ~«8 •s a « ^ •d ° B 9) normal development into the perfect adult form is impossible. The spermatic cell is the male element of reproduction; in most 742 SPECIAL PHYSIOLOGY animals, both vertebrate and invertebrate, the sperm cell is a flagellate cell whose head represents the nucleus and whose flagellum repre- sents the protoplasm. The male element being the active one in reproduction, the flagellum serves as a locomotory organ (Figs. 298 and 299). Fertilization may take place within the body of the female or external to it — internal or external fertilization. (Internal : most verte- brates. External: fishes, amphibia, and most invertebrates). (i) At fertilization only a single spermatozoon penetrates a sound egg, which occurs at the apex of the cone of attraction. (n) The head of the spermatozoon is converted into the spermatic nucleus, around which the neighboring protoplasmic granules are radially arranged (Fig. 300). (in) The egg nucleus and spermatic nucleus migrate toward each other and in most instances immediately fuse to form the segmentation nucleus (Figs. 301 and 302). Fertilization depends on the copulation of two cell nuclei which are derived from the male cell and a female cell. The male and female nuclear substances contained in the spermatic nucleus and egg nucleus are bearers of the peculiarities which are transmissible from parents to their offspring. 4. SEGMENTATION. Fertilization is in most cases immediately followed by further development which begins with the division of the egg cell into Segmentation of the vitellus in the impregnated egg of the rabbit. (Dalton, after Coste.) an ever-increasing number of ever-decreasing sized cells — the process of segmentation or cleavage (Fig. 303, A to F). EEPE OD UCTION 743 (a) INTERNAL PHENOMENA OF SEGMENTATION. 1st. The cleavage nucleus, at first spheroidal, forms the centre of a radiation which affects the whole yolk mass, but it soon begins to be slightly elongated, to become less and less distinct. The monocentric radiation is divided; the two newly formed radiations thereupon move to the poles of the elongated nucleus; they rapidly separate and finally each occupies a half of the egg. The nucleus while in the process of division consists of an acromatic and a chromatic figure — the former a spindle composed of a definite number of fibres, the latter the same number of V-shaped nuclear segments — chromosomes, which lie upon the surface of the middle of the spindle. 2d. The chromosomes split lengthwise and their halves move in opposite directions, apex first, to the polar centro- somes, where they form the daughter stars, later the daughter nuclei. (/?) EXTERNAL PHENOMENA OF SEGMENTATION consist in the division of the egg contents into cells, the number of which correspond to the number of nuclei. 5. THE EMBRYO. Beginning with a single cell — the egg cell — we have followed the development of a mass of cleavage cells— the morula, blastula, of which there are four forms. a. The Development of the Germ Layers. 1. The Blastula, with one germ layer. («) IN AMPHIOXUS the cleavage cavity is very large and its wall consists of a single layer of cylindric cells of nearly uniform size (Fig. 304, a). (/9) IN AMPHIBIA the cleavage cavity is small; the wall consists of a thin pole composed of small cells and a thick pole composed of several layers of large cells (Fig. 300, 6). (f) IN FISHES, REPTILES, AND BIRDS the cleavage cavity is fissure- like or wanting; the roof is the germ disk and the floor is the yolk mass, which is not divided into cells (Fig. 306, c). (o) IN MAMMALS — Man — the cleavage cavity is spacious and filled with albuminous fluid; the wall is a single layer of hexagonal cells, with the exception of one pole, whose larger cells in a mass extend into the cavity. 2. The Gastrula, with two germ layers. The invagination of the blastula forms the two layers of the gastrula; the outer layer is the ectoderm or epiblast; the inner layer is the entoderm or hypoblast; the cleavage cavity is obliterated; the invagination cavity is the coelenteron, its external mouth the primitive mouth, blastopore, primitive groove, or prostoma. 744 SPECIAL PHYSIOLOGY (a) IN AMPIIIOXUS the blastopore is large, the coelenteron capa- cious, each germ layer composed of a single sheet of cylindrical cells (Fig. 307). (/?) IN AMPHIBIA the blastopore is small, the mass of yolk cells is ventral to the coelenteron, which is arched upward and is fissure- like (Fig. 308). (7) IN FISHES, REPTILES, AND BIRDS the blastopore is crescentic ; the germinal disk becomes two-layered by means of ingrowth of cells from the blastopore. The coelenteron is ventral to the lower layer of cells — i. e., it is ventral to the hypoblast (Fig. 309). FIG. 304 FIG. 305 FIG. 306 The process of blastulation. a, blastula of Amphioxus ; b, blastula of triton (amphibian) ; c, blastula of bird ; c. c., cleavage cavity. (After Hertwig.) (o) IN MAMMALS the blastopore is minute and circular, and over a thickened pole the coelenteron and cleavage cavity are one and the same cavity. In all vertebrates the gastrula presents bilateral symmetry and anteroposterior differentiation; the blastopore is always posterior — dorso ventral differentiation — and the yolk mass is always ventral. 3. The Embryo, with three germ layers. In all vertebrates there are formed from the roof of the coelenteron two lateral evaginations of the inner germ layer or hypoblast, by REPRODUCTION 745 means of which the ccelenteron is divided into a median cavity— the intestine — and two lateral cavities, coelomic cavities, or body cavities. The primary inner germ layer thus becomes differentiated FIG. 307 FIG. 308 eel FIG. 309 The process of gastrulation. Gastrula of amphioxus (a) ; ot amphibian (6) ; of bird (c) ; of mammal (rabbit) (d) ; eel., ectoderm; ent., entoderm ; bl., blastopore or primitive mouth; cod., ccelenteron; d. 1., v. 1., dorsal and ventral lips; y. c., y.p., yolk cells and yolk plug; m, rneso- blast. (After Hertwig.) into : (i) The second inner germ layer — hypoblast. (n) Mesothelium of splanchnopleure and somatopleure. (in) Notochord. These are gradually separated from each other by constrictions. 746 SPECIAL PHYSIOLOGY The development — i. e., differentiation of the mesoblastic plates — takes place from before backward while the growth takes place at the blastopore, thus pushing the embryonal layers forward from that FIG. 310 point. During the growth of the mesoblast the blastopore has been metamorphosed into the primitive groove (Figs. 310 and 311). The primitive groove undergoes degeneration and is not converted into any organ in the adult. FIG. 311 The form of the blastopore and its metamorphosis in the chick embryo: a, blastopore of triton; b to e, blasto- pore of a chick gradually trans- formed from a transverse crescentic slit to a longitudinal groove— the primitive groove (e., p.g.). (After Hertwig.) FIG. 312 mp. ep. tTib. b. The Development of the Primitive Segments. In the mammals, birds, reptiles, amphibians, and fishes the meso- blast first appears as lateral somatic and splanchnic plates. At the time when these are constricted off from the coelenteron the free edges fuse and immediately thicken along the dorsum either side of REPRODUCTION 747 the notochord. This thickened plate is the primitive segment plate. Immediately after formation this segment plate begins segmentation, first in the trunk (30 to 50) and later in the head, eleven in number (Figs. 312 to 316). c. The Beginning of the Nervous System. The central nervous system of vertebrates is one of the first to be established after the separation of the germ into the three primitive TTlb. FIG. 314 ep. rnp. The derivation of the mesoblast and notochord from the primary inner germ layer (hypoblast). Cross-section of the amphioxus (308); of an amphibian (309); of a bird, 310), and of a mole (mam- mal) (d); ep., epiblast; mb., mesoblast; hy., hypoblast; cod., coelenteron; N, notochord. Note that in the amphibian (6) the mesoblast is pretty clearly divided into somatopleuric (am.) and splanchnopleuric mesothelium (sp.). (Hertwig, after Balfour, Heape, etal.) layers — epiblast, mesoblast, and hypoblast. It is developed out of a broad band of the epiblast, the medullary plate, which lies in the median line just over the notochord. Along this band the epiblastic cells become elongated and cylindric, while the remaining epiblast is composed of flattened plates joining by their edges. An evagination of the margins of the band forms the dorsal folds or medullary folds. A continuation of the evagination and a coalescence of the edges of the folds accomplishes a closure of the neural tube (Figs. 312 to 315). 748 SPECIAL PHYSIOLOGY The part of the neural tube which forms the brain becomes seg- mented early in the second day of incubation, twenty-fourth to thirtieth hour in the chick, into three primary brain vesicles : (i) the primary forcbrain vesicle, (n) the midbrain vesicle, (in) the primary hindbrain vesicle. Between the thirtieth and thirty-sixth hour of incubation the primary forebrain vesicle gives off two lateral evagi- nations — the optic vesicles- — and the primary hindbrain vesicle becomes divided into the cerebellar vesicle and the medullar vesicle. The closure of the neural tube or canal begins at the midbrain and progresses anteriorly over the forebrain and posteriorly over the cerebellar 'and medullar vesicles and proceeds along the spinal cord, finally closing it in at the posterior end (Fig. 315). Now it will be remembered that the blastopore, by virtue of the metamorphosis of the crescentic fold is now located at the anterior FIG. 315 Md Md Transverse section of the embryo chick, through closed portion of medullary canal. Mf, medullary canal; Eel, ectoderm; ent, entoderm; Md, Md', outer and inner laminse of meso- derm; p, peritoneal space; ch, chorda dorsalis; ao, aorta. (Kolliker.) end of the primitive groove. The closing of the neural canal posteriorly includes the anterior end of the primitive groove with the blastopore. It thus transpires that the blastoporic canal forms a direct communi- cation between the neural canal and the coelenteron or alimentary canal. This connection persists some time and is known as the neurenteric canal. It finally becomes obliterated through fusion of its walls. Thus the last vestige of the blastopore of the higher vertebrates becomes extinct in the early stages of embryonic develop- ment. d. The Mesenchyme. Soon after the formation of the primitive segments, these, which are at first solid, soon acquire a small cavity around which the cells are arranged into a continuous epithelium. The part of the wall REPROD UCTION 749 FIG. 316 lying at its lower median angle begins to grow with extraordinary rapidity and to furnish a mass of embryonic connective tissue which spreads itself around the cord and neural tube (Hertwig). Out of the dorsal and lateral parts of the primitive segment arises the trunk musculature. The mesenchyme arises from three other parts of the mesoblast besides the primi- tive segments, viz., (i) splanchnic mesothelium, (n) somatic meso- thelium, and (in) that wall of the primitive segment turned toward the epiblast. These four origins of the mesenchyme justify a classification of this important embryonic structure as (i) axial mesenchyme, (n) splanchnic me- senchyme, (m) somatic mesen- chyme, and (iv) dermal mesen- chyme. The method by which the mesenchyme arises is peculiar: (i) there is a rapid growth of the cells at some point in the meso- blast, accompanied by (n) a vigorous amoebqid movement. This combination makes in vagi- nation or evagination of a body of cells a mechanical impossi- bility; instead of that process, individual cells leave the parent epithelium and, by virtue of their continued amoeboid move- ments, wander between the soina- topleure and epiblast or between the splanchnopleure and hypoblast, as the case may be. The origin and destiny of the mesenchyme have been for more than a decade a riddle whose solution has engaged the attention of His, Kolliker, Heape, Waldeyer, and other embryologists. At the time of the formation of the inesciiclmuc end of first day in the chick — two necessities begin to press themselves upon tin- developing organisms: (i) necessity for mechanical support, and (ll) necessity for nutrition. The first of these necessities urges itself upon the axial part of the embryo, for there the delicate nervous system is passing rapidly through the steps of its development. The need for nutriment will not be felt by the epiblast or by the hypoblast, for these layers are next to the supply of nourishment; but by the Embryo chick, about the fortieth hour of incu- bation: Ce, cephalic extremity; Pv, primitive segments or protovertebne ; Dp, dorsal plates still widely separated in the caudal region; Pr, primitive groove. (Kolliker.) 750 SPECIAL PHYSIOLOGY mesoblast, in contact with neither white nor yolk. It is a law of biology that hungry organisms are restless, while satiated organisms are sluggish. Recall at this point the fact that the mesoblast cells which form the somatopleuric and splanchnopleuric mesenchyme free themselves from the mesoblast by dint of amoeboid movements. These restless hungry cells are out foraging. The leukocytes of the adult body are the descendants of these restless, hungry, foraging cells of the primitive mesenchyme. How are the two necessities mentioned above satisfied? («) THE NECESSITY FOR SUPPORT for the axial nervous system is satisfied by the axial mesenchyme which closes about the central nervous system and the notochord, and later develops into the axial skeleton with all its associated connective tissue. (/9) THE NECESSITY FOR NUTRIMENT is solved by the somato- pleuric and splanchnopleuric mesenchyme in the following manner, as represented by Kolliker and subscribed to by Hertwig: "At the end of the first day of incubation the masses of cells which represent the mesenchyme arrange themselves in cylindric or irregularly limited cords which join themselves together into a close-meshed network; they are the first fundaments, both of the bloodvessels and of their contents — the blood. In the spaces of the network are to be found groups of indifferent cells which afterward become embryonic connective tissues." In the beginning of the second day of incubation the "cords" acquire an internal cavity and become bounded super- ficially by a single layer of flattened polygonal cells — the future endothelium of the bloodvessels. "The cavity of the vessel is prob- ably formed by the penetration of fluid into the originally solid cord, thus forming the plasma of the blood by which the cells are pressed apart," some of these forming the vessel wall, some remaining floating in the fluid and becoming the leukocytes and red blood corpuscles. The red blood corpuscles originate, at the first, in the vascular area of the yolk, from yolk nuclei. They are nucleated during the early embryonic life of mammals and man and increase in numbers rapidly by division. e. The Origin of the Urinary System. Before the activities of life begin to make themselves manifest by the expenditure of energy, as in the transportation of matter through space — e. g., the action of the heart walls in the circulation of the blood — there is no need of an excretory system. If we admit, then, that the need for an excretory system arises during the third day in the chick, to what shall we attribute the actual appearance, during the second day, of a rudimentary urinary system? It must be attributed to HEREDITY. It is generally admitted that the genealogy of vertebrates extends through truncates back to worms. From your studies in zoology you recall the segmental organs of the higher REPRODUCTION 751 worms. A pair is located in each segment and each segmental organ is composed of (i) a ciliated funnel, (n) a convoluted tubule, (in) a glandular segment, and (iv) a muscular bladder which opens extern- ally. But this segmental arrangement of the excretory organs is an expensive and clumsy solution of the matter. In the lower vertebrates we see the following improvements: The uriniferous tubules are segmental, but instead of opening individually on the surface of the animal, as in worms, there is a collecting tube which transfers the secretion of all the tubules of one side of the body to a posterior and ventral orifice opening near or into the cloaca. In all the higher vertebrates, including man, the primitive kidney or pronephros is a segmental organ, and is quite rudimentary, never performing the function of excretion, even in the embryo. "THE PRONEPHROS of the chick is located between the seventh and eleventh somites. The pronephric duct, at its first appearance, is a short, canal-like per- foration of the wall of the body, which begins in the body cavity with one or several ostia and opens out upon the skin with but a single external orifice. Originally the outer and inner openings lie near together; later they move so far apart that the outer opening of the canal is united with the hindgut." (Hertwig.) /. Summary of Early Development. If the student has observed carefully the character of the develop- mental changes he has noted three phases of development going on at the same time: (i) The tendency to unequal groivth, manifested at particular places and occurring at particular times, resulting in the general morphologic unfolding; (11) the histologic differentiation manifesting itself in the development of new tissues (histogenesis) ; (HI) the physiologic division of labor, manifested by the general division of the functions into those of external relations and those of internal relations; and by the beginning development of various systems of organs — nervous system, circulatory system, excretory system, etc. («) THE PRINCIPLE OF UNEQUAL GROWTH is manifested in the chick during its first two days of development by: (i) the invagi- nation of the blastopore; (11) the evagination of the medullary folds; (HI) the evagination of the three primary brain vesicles from the anterior end of the neural tube; (iv) the subsequent evagination of the optic vesicles from the forebrain vesicle; (v) the evagination of the lateral folds of mesoblast from the median hypoblast; (vi) the separation of the muscle plates and their subsequent segmentation; (vn) the general emigration, from the mesoblast, of the elements of the mesenchyme; (vin) the invagination of the pronephric canals. 09) THE PRINCIPLE OF HISTOLOGIC DIFFERENTIATION is mani- fested in histogenesis: 752 SPECIAL PHYSIOLOGY HlSTOGENESIS. Origin of Tissues. I. ECTODERMIC TISSUES. Tissues of external relation. EPIBLAST PROPER. NERVOUS SYSTEM. Neuroblast. II. ENTODERMIC TISSUES. Tissues of internal relation. MESOBLAST. HYPOBLAST. NOTOCHORD. Cuticle and appendages, e.g., hair, nails, sebaceous and sweat glands, enamel of teeth. Epithelium of conjunctiva and cornea, nasal tract with glands, mouth with glands, anus and lower rectum, auditory canal. Central nervous system, i. e., brain and cranial nerves, spinal cord, and spinal nerves. Retina, cryst. lens, taste buds, auditory nerves, olfactory nerves, tactile bodies. Sensory apparatus. Primitive segments. Voluntary muscular sys- tem. Somatic pleura and Somatic J " peritoneum. Mesothelium. | Epithelium of genito- urinary tract. Splanchnic ! ±JUdl^'vleura" pericar' Mesothelium | Sp]anchnic peritoneum. CONNECTIVE TISSUES : Bone-cartilage, liga- ment, dentine, areo- lar tissue, tendon. Mesenchyme. \ INVOLUNTARY MUSCU- LAR SYSTEM. VASCULAR ENDOTHE- LIUM, BLOOD, AND SPLEEN. Epithelium of digestive tract (exclusive of mouth and anus). Inclusive of liver, pancreas. Epithelium of respiratory tract. urinary bladder and urethra. Eustacian tube and tym- pimum. tonsils, thymus body, thyroid body. 6. THE FETUS: ORGANOGENESIS. The terms fetus and embryo are used synonymously by some authors, while by others they are given different significations. Gould defines fetus as "the embryo in later stages of development," but uses embryo and fetus synonymously. The author, following in a general way the American Text-book of Obstetrics, will use the terms in the following sense: the embryo is the young in its early stages of development when tissues are being developed; the fetus is the young at a later stage of development when organs, especially systems of organs, are being given their finishing touches — i. e., the term embryo covers the period of histogenesis, and the term fetus covers the period of organogenesis. Under the caption fetus we shall briefly discuss the development of the various systems of organs. REPRODUCTION 753 a. The Circulatory System. 1. General Considerations. — («) THE SIMPLEST HEART among the vertebrates is a rhythmically contracting tube: the heart of the highest vertebrate is at first a rhythmically contracting tube. (p) INTERMEDIATE CLASSES OF VERTEBRATES have two- and three- chambered hearts, and the highest classes have the four-chambered FIG. 317 R.Com.Carotid I L.Com.Carotid R.Subclav. Superior Vena Cava 1.4 Duct.Art. Umbilical Vein ' Liver- Umbili, -Ext.Iliac Placenta Diagram of the fetal circulation. (Kirke.) heart: the heart of the highest vertebrate passes from the original tubular condition through the two- and three-chambered condition during fetal development and finally after birth assumes the function- ally four-chambered heart. 48 754 SPECIAL PHYSIOLOGY (?) THE ONE- AND TWO-CHAMBERED CONDITION OF THE HEART makes it necessary for the heart contractions to propel the blood in one circuit through a double system of capillaries: (i) the capil- laries of the respiratory system, and (11) the capillaries of the general circulation. The circulatory system of the highest vertebrates passes through this condition and reaches, in extrauterine life, a condition in which one-half of the heart propels the blood through the respiratory system while the other half propels it through the general system. CHANGE DURING PERIOD. CONDITION AT END OP PERIOD. I y II. CURVE of Heart-tube, through increase in length of Heart and no increase in length of pericardium. Heart in S-shaped curve, with venous end in left dorsal region and arterial end in right ventral region. II. m. DILATATION laterally of venous end and general DILATATION of central or ventracular segment and DILATATION of Bulbus Arteriosus. Heart of Two Chambers, one double- lobed, single-chamber auricle dor- sally and a single-chambered ven- tricle ventrally m. IV. DIVISION of whole Heart : 1st. Auricle into left and right. 2d. Ventricle into left and right. 3d. Bulbus Arteriosus into Aorta and Pulmonary Artery. Heart of FOUR Chambers. Left Au- ricle, Left Ventricle and Aorta con- tinuous and Right Auricle, Right Ventricle and Pulm. Art. continu- ous. IV. FIG. 318 Development of the heart. The four principal stages are shown at I to IV; a and 6 are two phases of the same stage. fHertwig.) (d) IN THE LOWER VERTEBRATES the blood passes from the heart directly into a system of branchial arches or gill-arches ; the highest vertebrate possesses this system of gall-arches during the early part of its development. These arches are gradually reduced during the three- and four-chambered stages. Our aortic and pulmonary arches represent the last two pairs of arches. (e) IN THE AMPHIBIA AND REPTILES, classes of vertebrates which possess three-chambered hearts, the purer blood passes to the anterior part of the body, while the less pure blood passes to the posterior part of the body. In the human fetus the functionally three-chambered heart distributes the blood in a similar way. This REPRODUCTION 755 probably accounts, in part, for the large head and small legs of the fetus (Fig. 317). 2. Special Metamorphosis of the Heart.— During the second day of the chick's development the heart is practically a straight tube formed by the fusion, along the median line, of a double, tubular heart fundament, continuous posteriorly with the two omphalo- rnesaraic veins and anteriorly with the bifurcated aorta. The endo- thelial partition of the heart soon disappears, leaving a single tube with somewhat thickened muscular walls. The dorsal aortse, in the mean time, pass laterally around thej alimentary canal and fuse FIG. 319 FIG. 320 FIG. 319.— Heart of the human fetus, at the end of the sixth month: a, inferior vena cava; b, superior vena cava; c, cavity of the right auricle, laid open from the front; d, appendix auricularis; e, cavity of the right ventricle; /, Eustachian valve. The bougie, placed in the inferior vena cava, can be seen passing behind the Eustachian valve, just below the point /, then crossing, behind the right auricle, through the foramen ovale to the left side of the heart. (Dalton.) FIG. 320.— Heart Of infant, showing disappearance of the artificial duct alter birth. 1, aorta; 2, pulmonary artery; 3, 3, pulmonary branches; 4, ductus arteriosus becoming obliterated. (Dalton.) ventrally, forming the single aortic trunk which joins the anterior end of the heart, or bulbus arteriosus. As soon as the posterior venous junctions and the anterior arterial junction has been effected the already slowly and irregularly beating heart begins to send the elements of the blood through the system of tubes, the direction of the stream being at first determined not by valves, but by virtue of a posteroanterior peristalsis. During the subsequent few hours the pulsations become regular and rapid, and the development of valves accompanies the gradual metamorphosis of the heart. The metamorphosis of the heart may be considered in four principal changes (Figs. 318, 319, and 320). 756 SPECIAL PHYSIOLOGY b. The Respiratory System. 1. General Considerations. — («) THE SIMPLEST VERTEBRATE respiratory system is composed of a series of gill-arches: The highest vertebrate has gill-arches in early embryonic life. (/?) IN THE HIGHEST FISHES there is a combination of gills and swim-bladder, which is a saccate evagination or outgrowth of the alimentary tract: In amphibia the gills are usually secondary in importance to the saccate lungs, which are homologous to the swim-bladder: In the highest vertebrate the gills are rudimentary structures confined to embryonic life, and never functional while the function of respiration is performed during the whole period of extrauterine life by the lungs. 2. Special. The Development of the Lungs.— At the beginning of the third day in the chick, on the tenth day in the rabbit, and in FIG. 321 u A B Early development of the lung: t, trachea; Oe, oesophagus; u, m, I, upper middle and lower right lobes; u', I', upper and lower left lobes; Spl., splanchnopleure; Ms., mesenchyme. (From Hertwig, alter His.) the human embryo when it reaches a length of about 4 mm., there arises on the ventral side of the oesophagus a groove which is slightly enlarged at its anterior end. Soon the groove-like evagination becomes separated from the alimentary tube by two lateral ridges; this is the first indication of a differentiation into oesophagus and trachea. There then grow out from the enlarged posterior ends of the groove two small sacs toward the two sides of the body — the fundaments of the right and left lung. These lung sacs are enveloped in a thick layer of mesenchymic connective tissue which is covered externally by the thin splanchnic mesothelium — the future lung-pleura. Two stages are recognizable in the metamorphosis of the primitive lung sacs of man and of mammals. REPRODUCTION 757 (i) The first bud-like outgrowths on the two sides of the body are not symmetric because the left lung sac produces two and the right lung sac produces three bud-like enlargements (Hertwig). These buds are the fundaments of the lobes of the lungs. From this point on the division is dichotomous. Continuous division and evagination proceed during six months in the human embryo. During this period the terminal branches are simply saccate or vesicular, and are called primitive lung vesicles (Fig. 321, B). (n) During the last three months of intrauterine life "there arise close together on the fine terminal of the bronchial tree — on the alveolar passages and on their terminal vesicular enlargements — very numerous small evaginations — the pulmonary alveoli" (Kolliker). These are only one-third to one-fourth as large in the fetus as in the adult, and the extrauterine growth of the lung is to be attributed to their expansion rather than to their multiplication. FIG. 322 c. The Digestive System. 1. General. — (a) IN ALL VERTEBRATES the stomach is produced by a simple dilatation of the alimentary canal, just behind the heart in the lower vertebrates and just posterior to the diaphragm in mam- malia (Fig. 322). (/9) IN ALL VERTEBRATES two glands are evaginated from the duo- denum—the liver is evaginated into the ventral mesentery and pancreas into the dorsal. 2. Special Development of Di- gestive Glands. — (a) THE LIVER early becomes bilobed — later these two primitive lobes are variously subdivided in different classes of vertebrates — and the evaginations take the form of thick-walled tubes or "hepatic cylinders" which unite into a network. The small lumina of the cylinders become the bile- ducts, which are surrounded by the secreting parenchyma of the liver. This latter, as well as the epithelial lining of all gall-ducts, is of hypoblastic origin, while the connective-tissue framework and the vascular system of the liver are from the mesenchyme, the organ being encapsuled with splanchnic peritoneum. (/9) THE PANCREAS follows a general course of development quite parallel to that of the liver. a b. c.
|
__label__pos
| 0.843077 |
Hence, only the classification of the elements themselves (amongst
concrete things), at present, depends largely upon empirical
Coinherence. If the elements remain irresolvable into anything simpler,
the definitions of the co-inherent characters that distinguish them must
be reckoned amongst the ultimate Uniformities of Nature. But if a
definite theory of their origin both generally and severally, whether
out of ether-vortices, or groups of electric corpuscles, or whatnot,
shall ever gain acceptance, similarity of genesis or causation will
naturally be the leading consideration in classifying the chemical
elements. To find common principles of causation, therefore, constitutes
the verification of every Natural Classification. The ultimate
explanation of nature is always causation; the Law of Causation is the
backbone of the system of Experience. CHAPTER XXII
NOMENCLATURE, DEFINITION, PREDICABLES
§ 1. Precision of thought needs precision of language for the recording
of such thought and for communicating it to others. We can often
remember with great vividness persons, things, landscapes, changes and
actions of persons or things, without the aid of language (though words
are often mixed with such trains of imagery), and by this means may form
judgments and inferences in particular cases; but for general notions,
judgments and inferences, not merely about this or that man, or thing,
but about all men or all kinds of things, we need something besides the
few images we can form of them from observation. Even if we possess
generic images, say, of 'horse' or 'cat' (that is, images formed, like
composite photographs, by a coalescence of the images of all the horses
or cats we have seen, so that their common properties stand out and
their differences frustrate and cancel one another), these are useless
for precise thought; for the generic image will not correspond with the
general appearance of horse or cat, unless we have had proportional
experience of all varieties and have been impartially interested in all;
and, besides, what we want for general thought is not a generic image of
the appearance of things, though it were much more definite and fairly
representative than such images ever are, but a general representation
of their important characters; which may be connected with internal
organs, such as none but an anatomist ever sees. We require a symbol
connected with the general character of a thing, or quality, or process,
as scientifically determined, whose representative truth may be trusted
in ordinary cases, or may be verified whenever doubt arises. Such
symbols are for most purposes provided by language; Mathematics and
Chemistry have their own symbols. § 2. First there should be "a name for every important meaning": (a) A
Nomenclature, or system of the names of all classes of objects, adapted
to the use of each science. Thus, in Geology there are names for classes
of rocks and strata, in Chemistry for the elements and their compounds,
in Zoology and Botany for the varieties and species of animals and
plants, their genera, families and orders. To have such names, however, is not the whole aim in forming a
scientific language; it is desirable that they should be systematically
significant, and even elegant. Names, like other instruments, ought to
be efficient, and the efficiency of names consists in conveying the most
meaning with the least effort. In Botany and Zoology this result is
obtained by giving to each species a composite name which includes that
of the genus to which it belongs. The species of Felidæ given in chap. xvii. § 7, are called _Felis leo_ (lion), _Felis tigris_ (tiger), _Felis
leopardus_ (leopard), _Felis concolor_ (puma), _Felis lyncus_ (European
lynx), _Felis catus_ (wild cat). In Chemistry, the nomenclature is
extremely efficient. Names of the simpler compounds are formed by
combining the names of the elements that enter into them; as Hydrogen
Chloride, Hydrogen Sulphide, Carbon Dioxide; and these can be given
still more briefly and efficiently in symbols, as HCl, H_{2}S, CO_{2}. The symbolic letters are usually initials of the names of the elements:
as C = Carbon, S = Sulphur; sometimes of the Latin name, when the common
name is English, as Fe = Iron. Each letter represents a fixed quantity
of the element for which it stands, viz., the atomic weight. The
number written below a symbol on the right-hand side shows how many
atoms of the element denoted enter into a molecule of the compound. (b) A Terminology is next required, in order to describe and define the
things that constitute the classes designated by the nomenclature, and
to describe and explain their actions. (i) A name for every integral part of an object, as head, limb,
vertebra, heart, nerve, tendon; stalk, leaf, corolla, stamen, pistil;
plinth, frieze, etc. (ii) A name for every metaphysical part or
abstract quality of an object, and for its degrees and modes; as
extension, figure, solidity, weight; rough, smooth, elastic, friable;
the various colours, red, blue, yellow, in all their shades and
combinations and so with sounds, smells, tastes, temperatures. The terms
of Geometry are employed to describe the modes of figure, as angular,
curved, square, elliptical; and the terms of Arithmetic to express the
degrees of weight, elasticity, temperature, pitch of sound. When other
means fail, qualities are suggested by the names of things which exhibit
them in a salient way; figures by such terms as amphitheatre, bowl-like,
pear-shaped, egg-shaped; colours by lias-blue, sky-blue, gentian-blue,
peacock-blue; and similarly with sounds, smells and tastes. It is also
important to express by short terms complex qualities, as harmony,
fragrance, organisation, sex, symmetry, stratification. (iii) In the explanation of Nature we further require suitable names for
processes and activities: as deduction, conversion, verification,
addition, integration, causation, tendency, momentum, gravitation,
aberration, refraction, conduction, affinity, combination, germination,
respiration, attention, association, development. There may sometimes be a difficulty in distinguishing the terms which
stand for qualities from those that express activities, since all
qualities imply activities: weight, for example, implies gravitation;
and the quality heat is also a kind of motion. The distinction aimed at
lies between a quality as perceived by means of an effect upon our
senses (as weight is resistance to our effort in lifting; heat, a
sensation when we approach fire), and that property of a body which is
conceived to account for its energy (as gravitation that brings a body
to the ground, or physical heat that expands an iron bar or works an
engine). The former class of words, expressing qualities, are chiefly
used in description: the latter class, expressing activities, are
chiefly needed in explanation. They correspond respectively, like
classification and explanation, with the static and dynamic aspects of
Nature. The terms of ordinary language fall into the same classes as those of
science: they stand for things, classes of things, parts, or qualities,
or activities of things; but they are far less precise in their
signification. As long as popular thought is vague its language must be
vague; nor is it desirable too strictly to correct the language whilst
the thought is incorrigible. Much of the effect of poetry and eloquence
depends upon the elasticity and indirect suggestiveness of common terms. Even in reasoning upon some subjects, it is a mistake to aim at an
unattainable precision. It is better to be vaguely right than exactly
wrong. In the criticism of manners, of fine art, or of literature, in
politics, religion and moral philosophy, what we are anxious to say is
often far from clear to ourselves; and it is better to indicate our
meaning approximately, or as we feel about it, than to convey a false
meaning, or to lose the warmth and colour that are the life of such
reflections. It is hard to decide whether more harm has been done by
sophists who take a base advantage of the vagueness of common terms, or
by honest paralogists (if I may use the word) who begin by deceiving
themselves with a plausible definiteness of expression, and go on to
propagate their delusions amongst followers eager for systematic insight
but ignorant of the limits of its possibility. § 3. A Definition is necessary (if possible) for every scientific name. To define a name is to give a precise statement of its meaning or
connotation. The name to be defined is the subject of a proposition,
whose predicate is a list of the fundamental qualities common to the
things or processes which the subject denotes, and on account of
possessing which qualities this name is given to them. Thus, a curve is a line of which no part is straight. The momentum of a
moving body is the product of its mass and its velocity (these being
expressed in numbers of certain units). Nitrogen is a transparent
colourless gas, atomic weight 14, specific gravity .9713, not readily
combining, etc. A lion is a monodelphian mammal, predatory, walking on
its toes, of nocturnal habits, with a short rounded head and muzzle;
dental formula: Incisors (3-3)/(3-3), canines (1-1)/(1/1), præmolars
(3-3)/(2-2), molars (1-1)/(1-1) = 30; four toes on the hind and five on
the fore foot, retractile claws, prickly tongue, light and muscular in
build, about 9-1/2 feet from muzzle to tip of tail, tawny in colour, the
males maned, with a tufted tail. If anything answers to this
description, it is called a lion; if not, not: for this is the meaning
of the name. For ordinary purposes, it may suffice to give an Incomplete Definition;
that is, a list of qualities not exhaustive, but containing enough to
identify the things denoted by the given name; as if we say that a lion
is 'a large tawny beast of prey with a tufted tail.' Such purposes may
also be served by a Description; which is technically, a proposition
mentioning properties sufficient to distinguish the things denoted, but
not the properties that enter into the definition; as if nitrogen be
indicated as the gas that constitutes 4/5 of the atmosphere. § 4. The rules for testing a Definition are: I.--As to its Contents--
(1) It must state the whole connotation of the name to be defined. (2) It must not include any quality derivative from the connotation. Such a quality is called a Proprium. A breach of this rule can do no
positive harm, but it is a departure from scientific economy. There is
no need to state in the definition what can be derived from it; and
whatever can be derived by causation, or by mathematical demonstration,
should be exhibited in that manner. (3) It must not mention any circumstance that is not a part of the
connotation, even though it be universally found in the things denoted. Such a circumstance, if not derivable from the connotation, is called an
Accident. That, for example, the lion at present only inhabits the Old
World, is an accident: if a species otherwise like a lion were found in
Brazil, it would not be refused the name of lion on the score of
locality. Whilst, however, the rules of Logic have forbidden the
inclusion of proprium or accident in a definition, in fact the
definitions of Natural History often mention such attributes when
characteristic. Indeed, definitions of superordinate classes--Families
and Orders--not infrequently give qualities as generally found in the
subordinate classes, and at the same time mention exceptional cases in
which they do not occur. II.--As to its Expression--
(4) A Definition must not include the very term to be defined, nor any
cognate. In defining 'lion' we must not repeat 'lion,' nor use
'leonine'; it would elucidate nothing. (5) It must not be put in vague language. (6) It must not be in a negative form, if a positive form be obtainable. We must not be content to say that a lion is 'no vegetarian,' or 'no
lover of daylight.' To define a curve as a line 'always changing its
direction' may be better than as 'in no part straight.'
§ 5. The process of determining a Definition is inseparable from
classification. We saw that classification consists in distributing
things into groups according to their likenesses and differences,
regarding as a class those individuals which have most qualities in
common. In doing so we must, of course, recognise the common qualities
or points of likeness; and to enumerate these is to define the name of
the class. If we discover the qualities upon which a class is based by
direct observation and induction, by the same method we discover the
definition of its name. We saw also that classification is not merely the determination of
isolated groups of things, but a systematic arrangement of such groups
in relation to one another. Hence, again, Definitions are not
independent, but relative to one another; and, of course, in the same
way as classes are relative. That is to say, as a class is placed in
subordination to higher or more comprehensive groups, so the definition
of its name is subordinate to that of their names; and as a class stands
in contrast with co-ordinate classes (those that are in the same degree
of subordination to the same higher groups), so the definition of its
name is in contrast or co-ordination with the definitions of their
names. Lion is subordinate to _Felis_, to Digitigrade, to Carnivore and
so on up to Animal; and, beyond the Animal Kingdom, to Phenomenon; it is
co-ordinate with tiger, puma, etc.; and more remotely it is
co-ordinate with dog, jackal, wolf, which come under _Canis_--a genus
co-ordinate with _Felis_. The definition of lion, therefore, is
subordinate to that of _Felis_, and to all above it up to Phenomenon;
and is co-ordinate with that of tiger, and with all species in the same
grade. This is the ground of the old method of definition _per genus et
differentiam_. The genus being the next class above any species, the _differentia_ or
Difference consists of the qualities which mark that species in addition
to those that mark the genus, and which therefore distinguish it from
all other species of the same genus. In the above definition of lion,
for example, all the properties down to "light and muscular in build"
are generic, that is, are possessed by the whole genus, _Felis_; and the
remaining four (size, colour, tufted tail, and mane in the male) are the
Difference or specific properties, because in those points the lion
contrasts with the other species of that genus. Differences may be
exhibited thus:
_Lion._ _Tiger._
SIZE: about 9-1/2 feet from nose | About 10 feet. to tip of tail. |
COLOUR: tawny. | Warm tawny, striped with black. TAIL: tufted. | Tapering. MANE: present in the male. | Both sexes maneless. There are other differences in the shape of the skull. In defining lion,
then, it would have been enough to mention the genus and the properties
making up the Difference; because the properties of the genus may be
found by turning to the definition of the genus; and, on the principle
of economy, whatever it is enough to do it is right to do. To define 'by
genus and difference' is a point of elegance, when the genus is known;
but the only way of knowing it is to compare the individuals comprised
in it and in co-ordinate genera, according to the methods of scientific
classification. It may be added that, as the genus represents ancestral
derivation, the predication of genus in a definition indicates the
remote causes of the phenomena denoted by the name defined. And this way
of defining corresponds with the method of double naming by genus and
species: _Felis leo_, _Felis tigris_, etc.; _Vanessa Atalanta_,
_Vanessa Io_, etc. The so-called Genetic Definition, chiefly used in Mathematics, is a rule
for constructing that which a name denotes, in such a way as to ensure
its possessing the tributes connoted by the name. Thus, for a circle:
Take any point and, at any constant distance from it, trace a line
returning into itself. In Chemistry a genetic definition of any compound
might be given in the form of directions for the requisite synthesis of
elements. § 6. The chief difficulty in the definition of scientific names consists
in determining exactly the nature of the things denoted by them, as in
classifying plants and animals. If organic species are free growths,
continually changing, however gradually, according as circumstances give
some advantage to one form over others, we may expect to find such
species branching into varieties, which differ considerably from one
another in some respects, though not enough to constitute distinct
species. This is the case; and, consequently, there arises some
uncertainty in collecting from all the varieties those attributes which
are common to the species as a whole; and, therefore, of course,
uncertainty in defining the species. The same difficulty may occur in
defining a genus, on account of the extent to which some of its species
differ from others, whilst having enough of the common character to
deter the classifier from forming a distinct genus on their account. On
the other hand the occurrence of numerous intermediate varieties may
make it difficult to distinguish genera or species at all. Even the
Kingdoms of plants and animals are hard to discriminate at the lowest
levels of organisation. Now, where there is a difficulty of
classification there must be a corresponding difficulty of definition. It has been proposed in such cases to substitute a Type for a
Definition; to select some variety of a species, or species of a genus,
as exhibiting its character in an eminent degree, and to regard other
groups as belonging to the same species or genus, according as they
agree more with this type than with other types representing other
species or genera. But the selection of one group as typical implies a
recognition of its attributes as prevailing generally (though not
universally) throughout the species or genus; and to recognise these
attributes and yet refuse to enumerate them in a definition, seems to be
no great gain. To enumerate the attributes of the type as an Approximate
Definition of the species or genus, true of _most_ of the groups
constituting the species or genus, answers the same purpose, is more
explicit, and can mislead no one who really attends to the exposition. An approximate definition is, indeed, less misleading than the
indication of a type; for the latter method seems to imply that the
group which is now typical has a greater permanence or reality than its
co-ordinate groups; whereas, for aught we know, one of the outside
varieties or species may even now be superseding and extinguishing it. But the statement of a definition as approximate, is an honest
confession that both the definition and the classification are (like a
provisional hypothesis) merely the best account we can give of the
matter according to our present knowledge. § 7. The limits of Definition are twofold: (a) A name whose meaning
cannot be analysed cannot be defined. This limitation meets us only in
dealing with the names of the metaphysical parts or simple qualities of
objects under the second requisite of a Terminology. Resistance and
weight, colour and its modes, many names of sounds, tastes, smells, heat
and cold--in fact, whatever stands for an unanalysable perception,
cannot be made intelligible to any one who has not had experience of the
facts denoted; they cannot be defined, but only exemplified. A sort of
genetic definition may perhaps be attempted, as if we say that colour is
the special sensation of the cones of the retina, or that blue is the
sensation produced by a ray of light vibrating about 650,000,000,000,000
times a second; but such expressions can give no notion of our meaning
to a blind man, or to any one who has never seen a blue object. Nor can
we explain what heat is like, or the smell of tobacco, to those who have
never experienced them; nor the sound of C 128 to one who knows nothing
of the musical scale. If we distinguish the property of an object from the sensation it
excites in us, we may define any simple property as 'the power of
producing the sensation'; the colour of a flower as the power of
exciting the sensation of colour in us. Still, this gives no information
to the blind nor to the colour-blind. Abstract names may be defined by
defining the corresponding concrete: the definition of 'human nature' is
the same as of 'man.' But if the corresponding concrete be a simple
sensation (as blue), this being indefinable, the abstract (blueness) is
also indefinable. (b) The second limit of Definition is the impossibility of exhausting
infinity, which would be necessary in order to convey the meaning of the
name of any individual thing or person. For, as we saw in chap. iv., if
in attempting to define a proper name we stop short of infinity, our
list of qualities or properties may possibly be found in two
individuals, and then it becomes the definition of a class-name or
general name, however small the actual class. Hence we can only give a
Description of that which a proper name denotes, enumerating enough of
its properties to distinguish it from everything else as far as our
knowledge goes. § 8. The five Predicables (Species, Genus, Difference, Proprium,
Accident) may best be discussed in connection with Classification and
Definition; and in giving an account of Classification, most of what has
to be said about them has been anticipated. Their name, indeed, connects
them with the doctrine of Propositions; for Predicables are terms that
may be predicated, classified according to their connotative relation to
the subject of a proposition (that is, according to the relation in
which their connotation stands to the connotation of the subject):
nevertheless, the significance of the relations of such predicates to a
subject is derivative from the general doctrine of classification. For example, in the proposition 'X is Y,' Y must be one of the five
sorts of predicables in relation to X; but of what sort, depends upon
what X (the subject) is, or means. The subject of the proposition must
be either a definition, or a general connotative name, or a singular
name. If X be a definition, Y must be a species; for nothing but a general
name can be predicated of a definition: and, strictly speaking, it is
only in relation to a definition (as subject) that species can be a
predicable; when it is called _Species predicabilis_ (1). If X be a connotative name, it is itself a species (_Species
subjicibilis_); and the place of the subject of a proposition is the
usual one for species. The predicate, Y, may then be related to the
species in three different ways. First, it may be a definition, exactly
equivalent to the species;--in fact, nothing else than the species in an
explicit form, the analysis of its connotation. Secondly, the predicate
may be, or connote, some _part only_ of the definition or connotation of
the species; and then it is either genus (2), or difference (3). Thirdly, the predicate may connote _no part_ of the definition, and then
it is either derivable from it, being a proprium (4), or not derivable
from it, being an accident (5). These points of doctrine will be
expanded and illustrated in subsequent pages. If X be a singular name, deriving connotation from its constituent terms
(chap. iv. § 2), as 'The present Emperor of China,' it may be treated as
a _Species subjicibilis_. Then that he is 'an absolute monarch,'
predicates a genus; because that is a genus of 'Emperor,' a part of the
singular name that gives it connotation. That he wears a yellow robe is
a proprium, derivable from the ceremonial of his court. That he is
thirty years of age is an accident. But if X be a proper name, having no connotation, Y must always be an
accident; since there can then be no definition of X, and therefore
neither species, genus, difference, nor proprium. Hence, that 'John Doe
is a man' is an accidental proposition: 'man' is not here a _Species
predicabilis_; for the name might have been given to a dog or a
mountain. That is what enables the proposition to convey information: it
would be useless if the proper name implied 'humanity.'
'Species' is most frequently used (as in Zoology) for the _class
denoted_ by a general name; but in Logic it is better to treat it as a
general name used connotatively for the attributes possessed in common
by the things denoted, and on account of which they are regarded as a
class: it is sometimes called the Essence (§ 9). In this connotative
sense, a species is implicitly what the definition is explicitly; and
therefore the two are always simply convertible. Thus, 'A plane
triangle' (species) is 'a figure enclosed by three straight lines'
(definition): clearly we may equally say, 'A figure enclosed by three
straight lines is a plane triangle.' It is a simple identity. A genus is also commonly viewed denotatively, as a class containing
smaller classes, its species; but in Logic it is, again, better to treat
it connotatively, as a name whose definition is part of the definition
of a given species. A difference is the remainder of the definition of any species after
subtracting a given genus. Hence, the genus and difference together make
up the species; whence the method of definition _per genus et
differentiam_ (_ante_, § 5). Whilst in Botany and Zoology the species is fixed at the lowest step of
the classification (varieties not being reckoned as classes), and the
genus is also fixed on the step next above it, in Logic these
predicables are treated as movable up and down the ladder: any lower
class being species in relation to any higher; which higher class,
wherever taken, thus becomes a genus. Lion may logically be regarded as
a species of digitigrade, or mammal, or animal; and then each of these
is a genus as to lion: or, again, digitigrade may be regarded as a
species of mammal, or mammal as a species of animal. The highest class,
however, is never a species; wherefore it is called a _Summum Genus_:
and the lowest class is never a genus; wherefore it is called an _Infima
Species_. Between these two any step may be either species or genus,
according to the relation in which it is viewed to other classes, and is
then called Subaltern. The _summum genus_, again, may be viewed in
relation to a _given_ universe or _suppositio_ (that is, any limited
area of existence now the object of attention), or to the _whole_
universe. If we take the animal kingdom as our _suppositio_, Animal is
the _summum genus_; but if we take the whole universe, 'All things' is
the _summum genus_. "Porphyry's tree" is used to illustrate this doctrine. It begins with a
_summum genus_, 'Substance,' and descends by adding differences, step by
step, to the _infima species_, 'Man.' It also illustrates Division by
Dichotomy. SUBSTANCE
/ \
CORPOREAL || INCORPOREAL
||
BODY
/ \
ANIMATE || INANIMATE
||
LIVING BODY
/ \
SENSIBLE || INSENSIBLE
||
ANIMAL
/ \
RATIONAL || IRRATIONAL
||
MAN
//||\\
// || \\
// || \\
// || \\
// || \\
// || \\
// || \\
_Socrates_ _Plato_ _Aristotle_
Beginning with 'Substance,' as _summum genus_, and adding the
difference 'Corporeal,' we frame the species 'Body.' Taking 'Body' as
the genus and adding the difference 'Animate,' we frame the species
'Living Body;' and so on till 'Man' is reached; which, being _infima
species_, is only subdivisible into individuals. But the division of Man
into individuals involves a change of principle; it is a division of the
denotation, not an increase of the connotation as in the earlier steps. Only one side of each dichotomy is followed out in the 'tree': if the
other side had been taken, Incorporeal Substance would be 'Spirit';
which might be similarly subdivided. Genus and species, then, have a double relation. In denotation the genus
includes the species; in connotation the species includes the genus. Hence the doctrine that by increasing the connotation of a name we
decrease its denotation: if, for example, to the definition of 'lion' we
add 'inhabiting Africa,' Asiatic lions are no longer denoted by it. On
the other hand, if we use a name to denote objects that it did not
formerly apply to, some of the connotation must be dropped: if, for
example, the name 'lion' be used to include 'pumas,' the tufted tail and
mane can no longer be part of the meaning of the word; since pumas have
not these properties. This doctrine is logically or formally true, but it may not always be
true in fact. It is logically true; because wherever we add to the
connotation of a name, it is possible that some things to which it
formerly applied are now excluded from its denotation, though we may not
know of any such things. Still, as a matter of fact, an object may be
discovered to have a property previously unknown, and this property may
be fundamental and co-extensive with the denotation of its name, or even
more widely prevalent. The discovery that the whale is a mammal did not
limit the class 'whale'; nor did the discovery that lions, dogs, wolves,
etc., walk upon their toes, affect the application of any of these
names. Similarly, the extension of a name to things not previously denoted by
it, may not in fact alter its definition; for the extension may be made
on the very ground that the things now first denoted by it have been
found to have the properties enumerated in its definition, as when the
name 'mammal' was applied to whales, dolphins, etc. If, however,
'mammal' had formerly been understood to apply only to land animals, so
that its definition included (at least, popularly) the quality of
'living on the land,' this part of the connotation was of course lost
when the denotation came to include certain aquatic animals. A proprium is an attribute derived from the definition: being either (a)
implied in it, or deducible from it, as 'having its three angles equal
to two right angles' may be proved from the definition of a triangle; or
(b) causally dependent on it, as being 'dangerous to flocks' results
from the nature of a wolf, and as 'moving in an ellipse' results from
the nature of a planet in its relation to the sun. An accident is a property accompanying the defining attributes without
being deducible from them. The word suggests that such a property is
merely 'accidental,' or there 'by chance'; but it only means that we do
not understand the connection. Proprium and Accident bear the same relation to one another as
Derivative and Empirical Laws: the predication of a proprium is a
derivative law, and the predication of an accident is an empirical law. Both accidents and empirical laws present problems, the solution of
which consists in reducing them, respectively, to propria and derivative
laws. Thus the colour of animals was once regarded as an accident for
which no reason could be given; but now the colour of animals is
regarded as an effect of their nature and habits, the chief determinants
of it being the advantage of concealment; whilst in other cases, as
among brightly coloured insects and snakes, the determinant may be the
advantage of advertising their own noxiousness. If such reasoning is
sound, colour is a proprium (and if so, it cannot _logically_ be
included in a definition; but it is better to be judicious than formal). If the colour of animals is a proprium, we must recognise a distinction
between Inseparable and Separable Propria, according as they do, or do
not, always accompany the essence: for mankind is regarded as one
species; but each colour, white, black or yellow, is separable from it
under different climatic conditions; whilst tigers are everywhere
coloured and striped in much the same way; so that we may consider their
colouring as inseparable, in spite of exceptional specimens black or
white or clouded. The same distinction may be drawn between accidents. 'Inhabiting Asia'
is an Inseparable Accident of tiger, but a Separable Accident of lion. Even the occasional characteristics and occupations of individuals are
sometimes called separable accidents of the species; as, of man, being
colour-blind, carpentering, or running. A proprium in the original signification of the term ἴδιον was peculiar
to a species, never found with any other, and was therefore convertible
with the subject; but this restriction is no longer insisted on. § 9. Any predication of a genus, difference or definition, is a verbal,
analytic, or essential proposition: and any predication of a proprium or
accident, is a real, synthetic, or accidental proposition (chap. v. §
6). A proposition is called verbal or analytic when the predicate is a
part, or the whole, of the meaning of the subject; and the subject being
species, a genus or difference is part, and a definition is the whole,
of its meaning or connotation. Hence such a proposition has also been
called explicative. Again, a proposition is called real or synthetic
when the predicate is no part of the meaning of the subject; and, the
subject being species, a proprium or accident is no part of its meaning
or connotation. Hence such a proposition has been called ampliative. As to Essential and Accidental, these terms are derived from the
doctrine of Realism. Realists maintain that the essence of a thing, or
that which makes a thing to be what (or of what kind) it is, also makes
everything else of the same kind to be what it is. The essence, they
say, is not proper to each thing or separately inherent in it, but is an
'Universal' common to all things of that kind. Some hold that the
universal nature of things of any kind is an Idea existing (apart from
the things) in the intelligible world, invisible to mortal eye and only
accessible to thought; whence the Idea is called a noumenon: that only
the Idea is truly real, and that the things (say, trees, bedsteads and
cities) which appear to us in sense-perception, and which therefore are
called phenomena, only exist by participating in, or imitating, the Idea
of each kind of them. The standard of this school bears the legend
_Universalia ante rem_. But others think that the Universal does not exist apart from particular
things, but is their present essence; gives them actuality as individual
substances; "informs" them, or is their formal cause, and thus makes
them to be what they are of their kind according to the definition: the
universal lion is in all lions, and is not merely similar, but identical
in all; for thus the Universal Reason thinks and energises in Nature. This school inscribes upon its banners, _Universalia in re_. To define anything, then, is to discover its essence, whether
transcendent or immanent; and to predicate the definition, or any part
of it (genus or difference), is to enounce an essential proposition. But
a proprium, being no part of a definition, though it always goes along
with it, does not show what a thing is; nor of course does an accident;
so that to predicate either of these is to enounce an accidental
proposition. Another school of Metaphysicians denies the existence of Universal Ideas
or Forms; the real things, according to them, are individuals; which,
so far as any of them resemble one another, are regarded as forming
classes; and the only Universal is the class-name, which is applied
universally in the same sense. Hence, they are called Nominalists. The
sense in which any name is applied, they say, is derived from a
comparison of the individuals, and by abstraction of the properties they
have in common; and thus the definition is formed. _Universalia post
rem_ is their motto. Some Nominalists, however, hold that, though
Universals do not exist in nature, they do in our minds, as Abstract
Ideas or Concepts; and that to define a term is to analyse the concept
it stands for; whence, these philosophers are called Conceptualists. Such questions belong to Metaphysics rather than to Logic; and the
foregoing is a commonplace account of a subject upon every point of
which there is much difference of opinion. § 10. The doctrine of the Predicaments, or Categories, is so interwoven
with the history of speculation and especially of Logic that, though its
vitality is exhausted, it can hardly be passed over unmentioned. The
predicaments of Aristotle are the heads of a classification of terms as
possible predicates of a particular thing or individual. Hamilton
(_Logic_: Lect. xi.) has given a classification of them; which, if it
cannot be found in Aristotle, is an aid to the memory, and may be thrown
into a table thus:
Substance οὐσία (1)
{Quantity ποσόν (2)
Attribute {Quality ποιόν (3)
{Relation πρόσ τι (4)
{ Where ποῡ (5)
{ When πότε (6)
{ Action ποιεῑν (7)
Modes of Relation { Passion πάσχειν (8)
{ Posture κεῑσθαι (9)
{ Habit ἔχειν (10)
Taking a particular thing or individual, as 'Socrates,' this is
Substance in the proper sense of the word, and can never be a predicate,
but is the subject of all predicates. We may assert of him (1) Substance
in the secondary sense (species or genus) that he is a man or an animal;
(2) Quantity, of such a height or weight; (3) Quality, fair or dark; (4)
Relation, shorter or taller than Xanthippe; (5) Where, at Athens; (6)
When, two thousand and odd years ago; (7) Action, that he questions or
pleads; (8) Passion, that he is answered or condemned; (9) Posture, that
he sits or stands; (10) Habit, that he is clothed or armed. Thus illustrated (_Categoriæ_: c. 4), the predicaments seem to be a list
of topics, generally useful for the analysis and description of an
individual, but wanting in the scientific qualities of rational
arrangement, derivation and limitation. Why are there just these heads,
and just so many? It has been suggested that they were determined by
grammatical forms: for Substance is expressed by a substantive;
Quantity, Quality and Relation are adjectival; Where and When,
adverbial; and the remaining four are verbal. It is true that the parts
of speech were not systematically discriminated until some years after
Aristotle's time; but, as they existed, they may have unconsciously
influenced his selection and arrangement of the predicaments. Where a
principle is so obscure one feels glad of any clue to it (_cf._ Grote's
_Aristotle_, c. 3, and Zeller's _Aristotle_, c. 6). But whatever the
origin and original meaning of the predicaments, they were for a long
time regarded as a classification of things; and it is in this sense
that Mill criticises them (_Logic_: Bk. I. c. 3). If, however, the predicaments are heads of a classification of terms
predicable, we may expect to find some connection with the predicables;
and, in fact, secondary Substances are species and genus; whilst the
remaining nine forms are generally accidents. But, again, we may expect
some agreement between them and the fundamental forms of predication
(_ante_, chap. i. § 5, and chap. ii § 4): Substance, whether as the
foundation of attributes, or as genus and species, implies the
predication of co-inherence, which is one mode of _Co-existence_. Quantity is predicated as equality (or inequality) a mode of _Likeness_;
and the other mode of _Likeness_ is involved in the predication of
Quality. Relation, indeed, is the abstract of all predication, and ought
not to appear in a list along with special forms of itself. 'Where' is
position, or _Co-existence_ in space; and 'When' is position in time, or
_Succession_. Action and Passion are the most interesting aspect of
_Causation_. Posture and Habit are complex modes of _Co-existence_, but
too specialised to have any philosophic value. Now, I do not pretend
that this is what Aristotle meant and was trying to say: but if
Likeness, Co-existence, Succession and Causation are fundamental forms
of predication, a good mind analysing the fact of predication is likely
to happen upon them in one set of words or another. By Kant the word 'Category' has been appropriated to the highest forms
of judgment, such as Unity, Reality, Substance, and Cause, under which
the understanding reduces phenomena to order and thereby constitutes
Nature. This change of meaning has not been made without a certain
continuity of thought; for forms of judgment are modes of predication. But besides altering the lists of categories and greatly improving it,
Kant has brought forward under an old title a doctrine so original and
suggestive that it has extensively influenced the subsequent history of
Philosophy. At the same time, and probably as a result of the vogue of
the Kantian philosophy, the word 'category' has been vulgarised as a
synonym for 'class,' just as 'predicament' long ago passed from
Scholastic Logic into common use as a synonym for 'plight.' A minister
is said to be 'in a predicament,' or to fall under the 'category of
impostors.'
CHAPTER XXIII
DEFINITION OF COMMON TERMS
§ 1. Ordinary words may need definition, if in the course of exposition
or argument their meaning is liable to be mistaken. But as definition
cannot give one the sense of a popular word for all occasions of its
use, it is an operation of great delicacy. Fixity of meaning in the use
of single words is contrary to the genius of the common vocabulary;
since each word, whilst having a certain predominant character, must be
used with many shades of significance, in order to express the different
thoughts and feelings of multitudes of men in endlessly diversified
situations; and its force, whenever it is used, is qualified by the
other words with which it is connected in a sentence, by its place in
the construction of the sentence, by the emphasis, or by the pitch of
its pronunciation compared with the other words. Clearly, the requisite of a scientific language, 'that every word shall
have one meaning well defined,' is too exacting for popular language;
because the other chief requisite of scientific language cannot be
complied with, 'that there be no important meaning without a name.'
'Important meanings,' or what seem such, are too numerous to be thus
provided for; and new ones are constantly arising, as each of us pursues
his business or his pleasure, his meditations or the excursions of his
fancy. It is impossible to have a separate term for each meaning; and,
therefore, the terms we have must admit of variable application. An attempt to introduce new words is generally disgusting. Few men have
mastered the uses of half the words already to be found in our classics. Much more would be lost than gained by doubling the dictionary. It is
true that, at certain stages in the growth of a people, a need may be
widely felt for the adoption of new words: such, in our own case, was
the period of the Tudors and early Stuarts. Many fresh words, chiefly
from the Latin, then appeared in books, were often received with
reprobation and derision, sometimes disappeared again, sometimes
established their footing in the language: see _The Art of English
Poetry_ (ascribed to Puttenham), Book III. chap. 4, and Ben Jonson's
_Poetaster_, Act. V. sc. I. Good judges did not know whether a word was
really called for: even Shakespeare thought 'remuneration' and
'accommodate' ridiculous. But such national exigencies rarely arise; and
in our own time great authors distinguish themselves by the plastic
power with which they make common words convey uncommon meanings. Fluid, however, as popular language is and ought to be, it may be
necessary for the sake of clear exposition, or to steady the course of
an argument, to avoid either sophistry or unintentional confusion, that
words should be defined and discriminated; and we must discuss the means
of doing so. § 2. Scientific method is applicable, with some qualifications, to the
definition of ordinary words. Classification is involved in any problem
of definition: at least, if our object is to find a meaning that shall
be generally acceptable and intelligible. No doubt two disputants may,
for their own satisfaction, adopt any arbitrary definition of a word
important in their controversy; or, any one may define a word as he
pleases, at the risk of being misunderstood, provided he has no
fraudulent intention. But in exposition or argument addressed to the
public, where words are used in some of their ordinary senses, it should
be recognised that the meaning of each one involves that of many
others. For language has grown with the human mind, as representing its
knowledge of the world: this knowledge consists of the resemblances and
differences of things and of the activities of things, that is, of
classes and causes; and as there is such order in the world, so there
must be in language: language, therefore, embodies an irregular
classification of things with their attributes and relations according
to our knowledge and beliefs. The best attempt (known to me) to carry
out this view is contained in Roget's _Thesaurus_, which is a
classification of English words according to their meanings: founded, as
the author tells us, on the models of Zoology and Botany, it has some of
the requisites of a Logical Dictionary. Popular language, indeed, having grown up with a predominantly practical
purpose, represents a very imperfect classification philosophically
considered. Things, or aspects, or processes of things, that have
excited little interest, have often gone unnamed: so that scientific
discoverers are obliged, for scientific purposes, to invent thousands of
new names. Strong interests, on the other hand, give such a colour to
language, that, where they enter, it is difficult to find any
indifferent expressions. _Consistency_ being much prized, though often
the part of a blockhead, _inconsistency_ implies not merely the absence
of the supposed virtue, but a positive vice: _Beauty_ being attractive
and _ugliness_ the reverse, if we invent a word for that which is
neither, 'plainness,' it at once becomes tinged with the ugly. We seem
to love beauty and morality so much as to be almost incapable of
signifying their absence without expressing aversion. Again, the erroneous theories of mankind have often found their way into
popular speech, and their terms have remained there long after the
rejection of the beliefs they embodied: as--lunatic, augury, divination,
spell, exorcism: though, to be sure, such words may often be turned to
good account, besides the interest of preserving their original sense. Language is a record as well as an index of ideas. Language, then, being essentially classificatory, any attempt to
ascertain the meaning of a word, far from neglecting its relations to
others, should be directed toward elucidating them. Every word belongs to a group, and this group to some other larger
group. A group is sometimes formed by derivation, at least so far as
different meanings are marked merely by inflections, as _short_,
_shorter_, _shorten_, _shortly_; but, for the most part, is a conflux of
words from many different sources. _Repose_, _depose_, _suppose_,
_impose_, _propose_, are not nearly connected in meaning; but are
severally allied in sense much more closely with words philologically
remote. Thus _repose_ is allied with _rest_, _sleep_, _tranquillity_;
_disturbance_, _unrest_, _tumult_; whilst _depose_ is, in one sense,
allied with _overthrow_, _dismiss_, _dethrone_; _restore_, _confirm_,
_establish_; and, in another sense, with _declare_, _attest_, _swear_,
_prove_, etc. Groups of words, in fact, depend on their meanings, just
as the connection of scientific names follows the resemblance in
character of the things denoted. Words, accordingly, stand related to one another, for the most part,
though very irregularly, as genus, species, and co-ordinate species. Taking _repose_ as a genus, we have as species of it, though not exactly
co-ordinate with one another, _tranquillity_ with a mental differentia
(repose of mind), _rest_, whether of mind or body, _sleep_, with the
differentia of unconsciousness (privative). Synonyms are species, or
varieties, wherever any difference can be detected in them; and to
discriminate them we must first find the generic meaning; for which
there may, or may not, be a single word. Thus, _equality_, _sameness_,
_likeness_, _similarity_, _resemblance_, _identity_, are synonyms; but,
if we attend to the ways in which they are actually used, perhaps none
of them can claim to be a genus in relation to the rest. If so, we must
resort to a compound term for the genus, such as 'absence of some sort
of difference.' Then _equality_ is absence of difference in quantity;
_sameness_ is often absence of difference in quality, though the usage
is not strict: _likeness_, _similarity_, and _resemblance_, in their
actual use, perhaps, cannot be discriminated; unless _likeness_ be the
more concrete, _similarity_ the more abstract; but they may all be used
compatibly with the recognition of more or less difference in the things
compared, and even imply this. _Identity_ is the absence of difference
of origin, a continuity of existence, with so much sameness from moment
to moment as is compatible with changes in the course of nature; so that
egg, caterpillar, chrysalis, butterfly may be identical for the run of
an individual life, in spite of differences quantitative and
qualitative, as truly as a shilling that all the time lies in a drawer. Co-ordinate Species, when positive, have the least contrariety; but
there are also opposites, namely, negatives, contradictories and fuller
contraries. These may be regarded as either co-ordinate genera or the
species of co-ordinate genera. Thus, _repose_ being a genus,
_not-repose_ is by dichotomy a co-ordinate genus and is a negative and
contradictory; then _activity_ (implying an end in view), _motion_
(limited to matter), _disturbance_ (implying changes from a state of
calm), _tumult_, etc., are co-ordinate species of _not-repose_, and
are therefore co-ordinate opposites, or contraries, of the species of
_repose_. As for correlative words, like _master and slave_, _husband and wife_,
etc., it may seem far-fetched to compare them with the sexes of the
same species of plants or animals; but there is this resemblance between
the two cases, that sexual names are correlative, as 'lioness,' and that
one sex of a species, like a correlative name, cannot be defined without
implying the other; for if a distinctive attribute of one sex be
mentioned (as the lion's mane), it is implied that the other wants it,
and apart from this implication the species is not defined: just as the
definition of 'master' implies a 'slave' to obey. Common words, less precise than the terms of a scientific nomenclature,
differ from them also in this, that the same word may occur in different
genera. Thus, _sleep_ is a species of _repose_ as above; but it is also
a species of _unconsciousness_, with co-ordinate species _swoon_,
_hypnotic state_, etc. In fact, every word stands under as many
distinct genera, at least, as there are simple or indefinable qualities
to be enumerated in its definition. § 3. Partially similar to a scientific nomenclature, ordinary language
has likewise a terminology for describing things according to their
qualities and structure. Such is the function of all the names of
colours, sounds, tastes, contrasts of temperature, of hardness, of
pleasantness; in short, of all descriptive adjectives, and all names for
the parts and processes of things. Any word connoting a quality may be
used to describe many very different things, as long as they agree in
that quality. But the quality connoted by a word, and treated as always the same
quality, is often only analogically the same. We speak of a _great_
storm, a _great_ man, a _great_ book; but _great_ is in each case not
only relative, implying small, and leaving open the possibility that
what we call great is still smaller than something else of its kind, but
it is also predicated with reference to some quality or qualities, which
may be very different in the several cases of its application. If the
book is prized for wisdom, or for imagination, its greatness lies in
that quality; if the man is distinguished for influence, or for courage,
his greatness is of that nature; if the storm is remarkable for
violence, or for duration, its greatness depends on that fact. The word
_great_, therefore, is not used for these things in the same sense, but
only analogically and elliptically. Similarly with good, pure, free,
strong, rich, and so on. 'Rest' has not the same meaning in respect of
a stone and of an animal, nor 'strong' in respect of thought and muscle,
nor 'sweet' in respect of sugar and music. But here we come to the
border between literal and figurative use; every one sees that
figurative epithets are analogical; but by custom any figurative use may
become literal. Again, many general names of widely different meaning, are brought
together in describing any concrete object, as an animal, or a
landscape, or in defining any specific term. This is the sense of the
doctrine, that any concrete thing is a conflux of generalities or
universals: it may at least be considered in this way; though it seems
more natural to say, that an object presents these different aspects to
a spectator, who, fully to comprehend it, must classify it in every
aspect. § 4. The process of seeking a definition may be guided by the following
maxims:
(1) Find the usage of good modern authors; that is (as they rarely
define a word explicitly), consider what in various relations they use
it to denote; from which uses its connotation may be collected. (2) But if this process yield no satisfactory result, make a list of the
things denoted, and of those denoted by the co-ordinate and opposite
words; and observe the qualities in which the things denoted agree, and
in which they differ from those denoted by the contraries and opposites. If 'civilisation' is to be defined, make lists of civilised peoples, of
semi-civilised, of barbarous, and of savage: now, what things are common
to civilised peoples and wanting in the others respectively? This is an
exercise worth attempting. If poetry is to be defined, survey some
typical examples of what good critics recognise as poetry, and compare
them with examples of bad 'poetry,' literary prose, oratory, and
science. Having determined the characteristics of each kind, arrange
them opposite one another in parallel columns. Whoever tries to define
by this method a few important, frequently occurring words, will find
his thoughts the clearer for it, and will collect by the way much
information which may be more valuable than the definition itself,
should he ever find one. (3) If the genus of a word to be defined is already known, the process
may be shortened. Suppose the genus of poetry to be _belles lettres_
(that is, 'appealing to good taste'), this suffices to mark it off from
science; but since literary prose and oratory are also _belles lettres_,
we must still seek the differentia of poetry by a comparison of it with
these co-ordinate species. A compound word often exhibits genus and
difference upon its face: as 're-turn,' 'inter-penetrate,'
'tuning-fork,' 'cricket-bat'; but the two last would hardly be
understood without inspection or further description. And however a
definition be discovered, it is well to state it _per genus et
differentiam_. (4) In defining any term we should avoid encroaching upon the meaning of
any of the co-ordinate terms; for else their usefulness is lessened: as
by making 'law' include 'custom,' or 'wealth' include 'labour' or
'culture.'
(5) If two or more terms happen to be exactly synonymous, it may be
possible (and, if so, it is a service to the language) to divert one of
them to any neighbouring meaning that has no determinate expression. Thus, Wordsworth and Coleridge took great pains to distinguish between
Imagination and Fancy, which had become in common usage practically
equivalent; and they sought to limit 'imagination' to an order of poetic
effect, which (they said) had prevailed during the Elizabethan age, but
had been almost lost during the Gallo-classic, and which it was their
mission to restore. Co-ordinate terms often tend to coalesce and become
synonymous, or one almost supersedes the other, to the consequent
impoverishment of our speech. At present _proposition_ (that something
is the fact) has almost driven out _proposal_ (that it is desirable to
co-operate in some action). Even good writers and speakers, by their own
practice, encourage this confusion: they submit to Parliament certain
'propositions' (proposals for legislation), or even make 'a proposition
of marriage.' Definition should counteract such a tendency. (6) We must avoid the temptation to extend the denotation of a word so
far as to diminish or destroy its connotation; or to increase its
connotation so much as to render it no longer applicable to things which
it formerly denoted: we should neither unduly generalise, nor unduly
specialise, a term. Is it desirable to define _education_ so as to
include the 'lessons of experience'; or is it better to restrict it as
implying a personal educator? If any word implies blame or praise, we
are apt to extend it to everything we hate or approve. But _coward_
cannot be so defined as to include all bullies, nor _noble_ so as to
include every honest man, without some loss in distinctness of thought. The same impulses make us specialise words; for, if two words express
approval, we wish to apply both to whatever we admire and to refuse both
to whatever displeases us. Thus, a man may resolve to call no one great
who is not good: greatness, according to him, connotes goodness: whence
it follows that (say) Napoleon I. was not great. Another man is
disgusted with greatness: according to him, good and great are mutually
exclusive classes, sheep and goats, as in Gray's wretched clench:
"Beneath the good how far, yet far above the great." In feet, however
'good' and 'great' are descriptive terms, sometimes applicable to the
same object, sometimes to different: but 'great' is the wider term and
applicable to goodness itself and also to badness; whereas by making
'great' connote goodness it becomes the narrower term. And as we have
seen (§ 3), such epithets may be applicable to objects on account of
different qualities: _good_ is not predicated on the same ground of a
man and of a horse. (7) In defining any word, it is desirable to bear in mind its
derivation, and to preserve the connection of meaning with its origin;
unless there are preponderant reasons for diverting it, grounded on our
need of the word to express a certain sense, and the greater difficulty
of finding any other word for the same purpose. It is better to lean to
the classical than to the vulgar sense of 'indifferent,' 'impertinent,'
'aggravating,' 'phenomenal.'
(8) Rigorous definition should not be attempted where the subject does
not admit of it. Some kinds of things are so complex in their qualities,
and each quality may manifest itself in so many degrees without ever
admitting of exact measurement, that we have no means of marking them
off precisely from other things nearly allied, similarly complex and
similarly variable. If so we cannot precisely define their names. Imagination and fancy are of this nature, civilisation and barbarism,
poetry and other kinds of literary expression. As to poetry, some think
it only exists in metre, but hardly maintain that the metre must be
strictly regular: if not, how much irregularity of rhythm is admissible? Others regard a certain mood of impassioned imagination as the essence
of poetry; but they have never told us how great intensity of this mood
is requisite. We also hear that poetry is of such a nature that the
enjoyment of it is an end in itself; but as it is not maintained that
poetry must be wholly impersuasive or uninstructive, there seems to be
no means of deciding what amount or prominence of persuasion or
instruction would transfer the work to the region of oratory or science.
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They are among the first vegetables that clothe the soil with verdure in newly formed countries, and they are the last that disappear when the atmosphere ceases to be capable of nourishing vegetation. The first green crust upon the cinders of Ascension consisted of minute Mosses ; they form more than a quarter of the whole Flora of Melville Island ; and the black and lifeless soil of New South Shetland is covered with specks of Moss struggling for existence.’ Their favourite localities, however, are those which are rich in decaying vegetable matter, and but little exposed to the sun’s lieat ; so that it is to the wood and forest, the deep ravine and the narrow valley, that the collector must look for his principal gatherings. The shady side of bold ridges must be carefully searched ; also damp hedgerows and wet rocky places, especially with a northern aspect, for in these many of the delicate Jungermannise love to grow. A few, comparatively rare, forms (the Splachna) choose the dung of animals as their habitat, principally in Alpine and Subalpine districts. ‘ One of these, Splachnum angustatum, which is commonly met with upon dung, we once saw growing vigorously upon the foot of an old stocking near the summit of Ingleborough, Yorkshire. The same species was found by a friend of ours covering the half- decayed hat of a traveller who had perished on the mountain of St. Bernard in Switzerland ; and the same, if we mistake not, was discovered by Captain Parry in Melville Island, vegetating in the bleached skull of a musk ox.’ * The Sphagna, as stated above, are truly aquatic, * Mascologia Britannica. OF THE MOSSES AND THEIR ALLIES. 141 choosing by preference the swamp and morass, great tracts of which they cover with their spongy tufts. They may be easily distinguished, even at a long distance, by their singular pale yellow hue, so different to the bright rich green which generally marks the Moss tribe. The denizens, however, of the water are far inferior in number to those which draw their nourishment from the atmosphere, thriving on the surface of rocks, damp walls, and stems of trees. Thus the Orthotricha are almost entirely confined to the latter habitat, the exceptions occurring on rocks, never on the naked soil. The collector, therefore, must take a rigid survey of the trees, as well as of the ground which they overshadow, taking particular care to examine the hollows formed by the junction of the branches with the stem ; also the base of the tree where the latter passes into the root and buries itself in the soil ; for it is in places of this description that the rain and dew settle, and consequently Mosses are encouraged to develop themselves. Uprooted trees, on which time and the weather are beginning to make an impression, are also favourite localities for nearly all the members of the Muscal alliance. Let them be closely investigated, for, other conditions being aus- picious, more examples will often be gathered here than hours of research will disclose in many less-favoured spots. A strong knife, a waterproof bag or small tin vasculum, a few small bottles, and a supply of paper, are all that is necessary, by way of outfit, for a 1 ramble among the Mosses.* If possible, only such specimens as are in full fructifi- cation should be gathered ; for, as a practical matter, mere tufts of leaves without signs of fruit, or with immature fruit, are really of very little value. So important is this, that, should the collector find himself in a neighbourhood where the Mosses do not yet display their fruit, he had far better leave them for a while, than gather them at once, however tempting the opportunity, or lovely the specimens. Let him mark the place carefully, and revisit it in a month or two, and in all probability he will be amply rewarded 142 OF THE MOSSES AND THEIR ALLIES. for his self-denial. Of course there are cases in which he has but little chance of seeing the spot a second time ; there is no help for him then but to secure the prize while he can. There are a few cases too in which the plants rarely, if ever, develop their organs of fructification. Here again he must ‘ take things as he finds them ; ’ it would be of no use to wait, and he must be satisfied with sterile examples. [The reproductive organs of Mosses consist of so-called antheridia and pistillidia, or archegones. The former are minute globular or oval bodies, supported on a short pedicel, and, when ripe, discharging a granular matter, which has been likened to pollen. They are usually associated with a number of jointed cellular filaments or paraphyses, the 1 fila succulenta * of Hedwig. These antheridia are considered to be the representatives of the stamens, or male organs of the flowering plants. The pistillidia, on the other hand, minute flask-shaped bodies, swollen at the base, are looked upon, as their name implies, as corresponding to the pistils, or female organs of the Phanerogamia. By degrees they are developed into the long stemmed capsule, or theca, so conspicuous in most Mosses by their bright chestnut colour. Now it is requisite, if possible, that the student should provide himself with examples of each of these organs, not only because of the interest attached to them, but from the increasing tendency of museologists to base their systems of classification on these minute structures. — Ed.] It frequently happens, however, that Mosses are dioe- cious ; that is to say, the two kinds of reproductive organs are situated on separate plants, the mature female of course being the most conspicuous. This is exactly analogous to what occurs among the true sexual plants ; but then their parts, as a rule, are evident enough, whereas among the Mosses and their allies the same parts, at any rate at first, are strictly microscopic. All we can recommend to the student is, to make diligent search. If the antheridia are not to be found in the 1 pistillidiferous ’ specimens, he should Plate XIX. 96. Torrubia sphingum, fertile stipe. 97. Torrubia etylophora. 98. Morchella esculenta. 99. Lycoperdon gemmatum. OF THE MOSSES AND THEIR ALLIES. 145 examine the neighbourhood (especially where it varies a little in elevation or dampness) for male plants. ‘ Practice makes perfect,’ and though frequent disappointments may occur, success will follow, in a greater or less degree, as he applies himself more vigorously to his work. In gathering the Hepaticse it is indispensable to secure the organs of fructification : these are of simpler structure and lower organisation than in the Mosses, consisting of capsules either imbedded in the thick cellular frond (the Iticcise), or elevated on footstalks (Marchantia, Junger- mannia, &c.), but in either case unprovided with the calyptra and operculum, the hoods which distinguish and protect the spore cases of the true Mosses. When then the latter plants are placed in the bag or vasculum, precautions must be taken against losing the hoods, as they are of great service in the elucidation of genera, and unhappily they are very apt to drop off— [I always myself * bottle ’ a few small specimens, the enclosed moisture preventing the separation of the calyptra from the theca. The leaves too are kept fresh and the plants generally are saved from rubbing and consequent mutilation. This refers more particularly to the Jungermannise, the extreme delicacy of whose fruit, and stem, and leaves demand most tender treatment. The ‘ bottling * also ensures a specimen being ready for examination immediately on returning home ; though this is by no means essential, as all the Moss tribe speedily recover their plumpness and general appearance, on being immersed in water, after they have been lone: dried.— Ed.] 6 They are very easily prepared for the herbarium, all that is necessary being to separate them into convenient portions, pick out all foreign bodies (such as fragments of leaves, &c.), place them between blotting-paper, and sub- mit them to the press. The weights employed must be of the lightest, as otherwise the natural appearance of the plants are distorted. The true Mosses are usually divided into two chief sections — the Acrocarpi, or those in which L 146 OF THE MOSSES AND THEIR ALLIES. the fruit is situated at the summit of a stem, and the Pleurocarpi, which bear the fruit on the sides. In one word, in the first, the theca or capsule is terminal; in the second it is lateral. This difference of structure necessitates a difference of treatment in preparation. Bunches of the lateral fruited species may be separated by the hand without taking the trouble to isolate individual plants : it is better, in fact, to leave them massed together, as showing their character of growth more accurately. With the terminal fruited species, on the contrary, the natural habit of the plants is seen better if they are separated, though they need not be entirely so. For this purpose, two or three clean cuts may be made with a knife through the tuft, from above downwards, thereby making thin sections held together slightly at the bottom, either by the adherent earth, or by their own interwoven roots. Some of the very delicate kinds, such as Brachyodus or Seligeria, and many of the Jungermannise should be collected together with the bark or stone to which they have at- tached themselves. The Hepaticse need great care in their preparation ; not the least difficulty is the getting rid of the soil from their roots without injuring the leaves or breaking the stem. The best method of accomplishing this is to lay the plants, just as they are brought home, in a cup of clean water, then, by a gentle movement of the fluid backwards and forwards, the earth will gradually separate itself and settle at the bottom. The water should be constantly renewed, until no signs of discoloration appear. Next let the plant be carefully lifted out of the cup and laid on soft paper to allow of the water draining off. Here, again, great care is needed, because some of the important parts are easily broken off and lost from their extreme minuteness, if any roughness or over-haste is used; such are the so-called gemmae, the calyx or vaginule, and the antheridia, on their short pellucid footstalks. An ordinary lens is sufficient for the examination of the stems and branchlets of the Mosses ; but the construction of OF THE MOSSES AND THEIR ALLIES. 147 the leaf (especially in the Hepaticse) can only be properly seen with a microscope whose powers are not less than 200 diameters. For this purpose a leaf must be separated, by means of a pair of forceps, quite close to the stem, or the stem itself may be divided above and below the point of attachment, and the whole section submitted to the micro- scope. This last is perhaps the better arrangement, be- cause it often happens that the base of the leaf is furnished with peculiar cells, which are of service in discriminating species. A drop of water should be added to the leaf, when it is laid on the slide, as this renders the delicate network of cells more pervious to light. I have found the following plan bring out the form of the cells of the Jungermannise, and indeed of many of the Mosses, very clearly. First, let the leaflet be warmed to ebullition in a solution of caustic potash, rinse it in soft water, and then add a drop of a solution of chloride of zinc and iodine. By this means the cell walls, after a while (though sometimes not for hours), assume a blue tint, and on being slightly pressed under the covering glass, the layers of cellular tissue exhibit themselves to great perfection. The arrangements, however, of the leaf cells may be best seen in vertical sections, made by means of a divided cork in the way recommended at p. 129. In many cases the necessity for preparing these thin sections is not called for, while in others (as Fissidens, Polytrichum, Sphagnum, &c.) the true construction of the leaf cannot be made out without them.* * The following observations on the leaves of the Jungermannise are of value : — ‘ The leaves are remarkably varied in their form and arrangement, and usually afford excellent guides in the discrimina- tion of one species from another. A glance at the figures which follow will show their great variation in this particular. ... In all cases the leaves are without footstalks, and in each British species alternate ; that is, they are not arranged in pairs at the same level on the stem, but one is always a little above or below its nearest neigh- bour in its attachment. In some cases they are ranged in two row® 148 OF THE MOSSES AND THEIR ALLIES. The amphigastria are a kind of modified leaves in the Hepatic^, answering in some respects to the stipules of more perfect plants. Growing, as they do, on the lower surface of the stem, and being very minute, considerable trouble is involved in searching for them, as numerous stems have to be examined ; neither are they always pre- sent over the whole extent of the stem. The most likely parts are healthy young shoots, especially those that sup- port the reproductive organs. The eye, too, should be directed to the sides of the under-surface, rather than along the central axis. For the purpose of examination the amphigastrise may be shaved off with a thin and very sharp penknife, or the stem itself may be divided, as directed for the true leaves. The latter method has the advantage of securing the stipule from injury, and of giving a good insight into its mode of attachment. on opposite sides of the stem. In other and fewer instances they are attached to, or grow from, all sides of the stem. It is of rare occur- rence to find the leaves notched at the margin, hut this sometimes takes place. The cells, of which the leaves are composed, are roundish, or hexagonal, from pressure, and very variable in size. This also is a great assistance in the determination of species. . . . The cells of the ladder scale Moss (Alicularia scalaris), for instance, contain peculiar nucleate bodies of from two to four granules in a hne in each of the cells (fig. 2) ; those of the three- toothed scale Moss (Pla- giochila tridenticulata) fig. 3, and of the curled-leaved scale Moss (Jungermannia curvifolia), fig. 4, will illustrate some of the forms of leaf cells.’ (‘ British Hepaticse ; an Easy Guide to the Study of,’ by M. C. Cooke — a work which piay be consulted with advantage by the student. It is crowded with figures, and its exceedingly low price places it within every one’s reach.) — Ed. OF THE MOSSES AND THEIR ALLIES. 149 The vagimile, which answers to a certain extent to the calyx of the Phanerogamia, at first encloses the spore-case ; the latter, however, soon bursts through its cellular en- velope, and is elevated on a delicate threadlike stem. The vaginule should be examined in its early state, previous to its losing its contents, first from the exterior ; and, when its outward form is familiar to the observer, he should divide it under water into two halves longitudinally, in one of which he will see the organs of fructification in a greater or less degree of development. Ordinarily this division of the vaginule may be easily effected by means of a forceps in each hand ; occasionally it is of so fleshy a nature as to allow of being cut with a knife. For studying the anatomical structure of the fruit of the Mosses a capsule must be taken with the fruit not yet ripe. Thin sections, vertical and horizontal, may be made with great ease. A peculiar organ is found in the capsules of nearly all the Hepaticse, called the elater. It is a single or double filament, spirally twisted, and enveloped in a slender tube : both tube and elater form interesting objects for the microscope. Of what service the elaters may be in the economy of the plant is not yet accurately ascertained ; their probable office is to disperse the spores by their elas- tic movement as soon as the latter are ripe. A still more mysterious organ found in the antheridia of most of the Mosses is the spermatozoid, or antherozoid, or spermatic filament ; for by all these names it is known among botanists. It is a minute thread, of ■which the functions are not yet known. On being placed in water these spermatozoids exhibit active spontaneous motion, as may be seen by squeezing the contents of a ripe antheridium into a drop of water on a slide, covering it with thin glass, and then submitting it to a microscope with a power of from 300 to 600 diameters. If the movements are too quick for observation, they may be retarded by allowing a drop of iodide solution to make its way under the covering glass. * 150 OF THE MOSSES AND THEIR ALLIES. For the determination of species the capsule and its enclosed spores must be quite ripe, and must still retain its operculum (or lid), and calyptra (or veil'). A few species (as Phascum) are destitute of an operculum ; and in some (as Sphagnum) the calyptra disappears long before the capsule reaches maturity. In all cases however,, where they are present, both lid and veil drop off as soon as the spores are ready for dispersion ; an office which is greatly assisted by a third organ, which crowns the capsule,, and is known as the fringe or peristome. This last, which is sometimes single and at others double,, is of the utmost importance in the discrimination of genera ; so much so that, in systematic works, the characters of the subsections are founded on its absence or presence ; and the Aploperistomi (plants with a single fringe), the Diplo- peristomi (those with a double fringe), and the Gymno- stomi (or such as are destitute of a fringe), form acknow- ledged divisions in the Muscat family. The peristome, moreover, from its peculiar construction and delicate colouring, makes a lovely object for the micro- scope. A specimen is easily prepared : lay the capsule on the thumb-nail of the left hand and cut it across the shorter axis with a sharp knife, rather towards the summit. The upper portion, which now represents a short tube, is next to be cut half through vertically. The fringe may then be spread out on a slide and covered with a thin glass to pre- vent it from again curling up. The leaves may be preserved for future observation by laying them between two pieces of thin glass, united at the edges by asphalte. When wanted for use the specimen is- dipped into water, which entering between the glasses moistens the leaf, and restores it temporarily to its original appearance. All the more important organs may be treated in the same way. By this arrangement much time is saved, when it is desired to examine any particular species, of which perhaps there may be but few examples- in the herbarium, and the specimens themselves, preserved Plate XX. 100. Lycoperdon saccatum. 101. Lycoperdon atropurpureum. OF THE MOSSES AND THEIR ALLIES. 153 between the sheets of paper, are saved from the wear and tear to which they would be subjected if constantly brought out for investigation. I am of opinion, that if the specimens were mounted in silicate of potash (or waterglass, as it is sometimes called), much future time and trouble would be saved, as the leaf would probably retain its fair appearance without being immersed in water every time it was wanted. But my own experience is not sufficient to justify me in recom- mending it to others. [I have frequently employed silicate of potash as a preservative medium for the leaves of Mosses and other objects. In some instances it has suc- ceeded thoroughly, the leaflets retaining their fresh appear- ance, and remaining unaltered. But it appears to be un- certain in its action, 4 vacuoles ’ and bubbles often appear- ing in its midst in the most unaccountable manner. For pleasantness in using, rapidity in drying, &c., it surpasses any medium with which I am acquainted. — Ed.] 154 OF THE FERNS AND FLOWERING PLANTS, CHAPTER XV. OF THE FERNS AND FLOWERING PLANTS. I have thought it as well to unite these two classes, not only on account of the external resemblance which they bear to each other (as compared with the preceding- families), but because, speaking generally, the same method, of preparation are applicable to both. As a rule, Ferns, especially the commoner sorts, are far better known to the botanical student, than any of the Cryptogamic orders, not excepting the Algae. Their bright green colouring and the graceful outline of their fronds invite the attention of the passer-by ; and many a beginner glories in a collection of dried Ferns, who has never troubled himself about their specific or even generic differences. These depend almost exclusively upon the fructification, the absence or presence of an indusium, the form of the spore-case and its ring, and the shape of the sorus or collected spore-cases. It would be beside the object of this Handy -book to enter into this subject, nevertheless the accompanying plates (xxv. and xxvi.) will assist the student in discriminating some of the genera more commonly met with ; the glossy Hartstongue (xxv. 110), and scaly Ceterach (111), the glorious flower- ing Fern (xxvi. 112), and its humble relative theAdders- tongue (113). For a more intimate knowledge of the structural differences in this interesting family I must refer the reader to John Smith’s ‘ Ferns, British and Foreign,’ and to the works of Newman, Moore, and other well-known Pteridologists. If it were necessary to warn the student to secure perfect examples of the more lowly organised plants — the Algae, Fungi, Lichens, and Mosses — still more needful is it to OF THE FERNS AND FLOWERING PLANTS. 155 repeat the warning here. Among the Phanerogamia, with very rare exceptions, flower and fruit, leaves, stem and root, are fully developed ; and (excluding the first-named) they are equally perfect in the Ferns. Consequently every one of these organs ought to find a place in the herbarium. There is no positive reason why the stem, or the root, should be neglected any more than the flower, or the leaf. And yet this is just the point in respect to which beginners make the most w-oful mistakes. They are satisfied with a moiety, when they should have the whole. An her- baceous plant, for instance, is plucked off at some distance above the junction of the stem with the root, and carried triumphantly home as a specimen of that particular species. What is the result ? Suppose it is an Orchis which the tyro has in hand. He searches through one or the other of the standard botanical works, and, under the head of Orchis, he finds that the specific differences depend in a greater or less degree on the form of the root : thus, while one important subdivision has ‘ tubers undivided/ another is provided with ‘ palmate tubers.’ Hence he is reduced to guess at the name of his fragment, or at best to do his work of collecting over again — not always a convenient task. The fact is, there are peculiarities in every part of a plant, from the root to the inflorescence, which cannot be neglected with impunity. What a large number of species depend for their due identification upon the presence of the radical or root leaves, and which cannot be satisfac- torily determined, unless these are under the observer’s eye ! The very names of some are based upon the fact of the root-leaves having a totally different form to the series which clothe its upper parts. It is well known that the stem-leaves of the common hare-bell are narrow and linear. Whence then its technical name, Campanula rotundifolia ? It was given to it by the great Linnagus, who saw it in the early summer forcing its way through the chinks of some stone steps in the university of Upsal. At that season the 156 OF THE FERNS AND FLOWERING PLANTS crown of the root is encircled by round or cordate leave which quickly decay and vanish ; hence the origin of its specific title. Here then is a case in point, illustrating the need of gather- ing examples of all the leaves, radical and cauline alike. There are certain families also, like the Roses and Brambles, in which the leaves vary much in form according to the part of the plant on which they grow. Specimens of these variations must be gathered, if the student hopes to have at all a satisfactory collection. Where the plants are either monoecious or dioecious, it stands to reason that both the sexes must be secured, whether found on separate individuals, or on different parts of the same plant. The fructification plays a most important part among both generic and specific characteristics. What, for instance, is the value of a flower, taken alone, among the Crucifer® and Umbellifer® ? Almost nil ! It is to the fruit that we have to look to bring order out of chaos, and settle the limits of genera. In a modified degree the same may be said of other families. As many species flower through a large part of the year, there is seldom any difficulty in securing with the flower the half-developed fruit, which should be noted down and again visited at a later period, when the seed- vessel is mature. The Crucifer®, except in their earliest stage, are tolerably certain to supply the collector with both flowers and fruit — the latter in a more or less advanced con- dition— the ripest at the base of the stem, and so passing through every stage up to the barely opened corolla. Another group of plants, which has to be carefully watched, are those trees and shrubs in which the flowers are produced on naked branches, the leaves not appearing until some time after the flowers themselves have withered away. Of course, in such instances, flower and leaf must be gathered on different occasions. Only let the collector be careful to take the latter from the same specimen, fiom OF THE FERNS AND FLOWERING PLANTS. 157 which he has already gathered the flower. The same foresight must be extended to the fruit. The latter, indeed, is not indispensable, though certainly desirable ; for the reader may easily picture to himself what confusion and errors may possibly arise, where there is no certainty of the examples, which lie together in the herbarium, having been the produce of the same plant. The above remarks refer with tenfold force to the Willows, which seem to have a peculiar facility for hybri- dising ; and, therefore, the greatest care should be taken to isolate every specimen, and if possible to have it in one’s power to identify the very tree from which each was taken. The Ferns are no exception to the rule, which demands that the plant should be seen in its integrity when dried. The crown and root must always, if possible, be secured as well as the frond ; and of the latter, those which have no fruit on them must not on that account be passed by, as the two kinds often exhibit wide differences in form, and mark the character of the plant. More than one species of the remarkable genus, Equisetum, is furnished with both sterile and fertile fronds ; both of which must of course be gathered and laid side by side in the herbarium. In the case of the common Equisetum arvense, the succulent, fawn-coloured, fruit-bearing stem rises upright from the soil weeks before the harsh green procumbent frond spreads itself over the ground. In others again the fertile shaft is entirely unbranched, while the sterile stems are enriched by frequent whorls of elegant pendant branches. The two sorts of frond may be easily recognised ; while the barren stem tapers gradually to a point, the fertile is furnished with a stout clavate head, which is in fact the receptacle, and contains the spores in a number of separate sporangia. These spores are themselves very interesting objects : each is furnished with four filamentous processes, known as elaters, though very unlike the elaters which are mingled with the spores in the capsules of the Hepaticse. They are extremely sensitive to the influence of moisture, 158 OF THE FERNS AND FLOWERING PLANTS. and, if breathed upon while under the microscope, will be seen to curl and uncurl themselves, enfolding the spore or causing it to dart on one side. The collector is well prepared for a botanical expedition when he has furnished himself with a common gardener’s trowel, a strong knife (if provided with a saw so much the better), and a tin vasculum, the latter larger or smaller according to the probable duration of his trip, the time of year, the plants likely to be met with, &c.* If, on returning home, the dowers have closed their petals, as frequently happens, it is only necessary to set the roots in a basin of water, until the corollas have again opened, when the roots may be roughly dried, and the preservation of the plant proceeded with. Should they be wet from dew or rain, when gathered, they must be laid by until every trace of moisture has disappeared ; other- * A very -useful instrument was brought under my notice, many years ago, by that eminent botanist, Philip Barker Webb. The ac- companying figure exhibits its general form. The total length is 15 inches, of which the handle occupies rather more than one-third. The blade (which is triangular in shape 1 14 - each side of the triangle measuring seven-eighths of an inch where it joins the handle) is brought to an obtuse point. About midway between the two extremities, or, more correctly speaking, some 4^ inches below the handle, it begins to make a gentle curve, the lower end being about one inch out of the true line. One of the angles forms the back of the curve. For convenience of carriage it should be fitted into a stout leather case. This instrument, which was Mr. Webb’s invariable com- panion in his numerous Alpine excursions, is of great value for forcing plants from between the fissures of rocks, massive tree roots, &c. ; in a word, from places where the broad surface of a trowel cannot be inserted, or would probably be broken, if it could be got in at all. It is also useful for extracting tap roots without injury or any other hard dry soil. If made of good material, it will last a lifetime. My own has seen a good deal of rough service, but is practically in as good condition as when it was made twenty years ago. — E d. from chalk Plate XXI, 102. Aregma bulbosum. 10-3. Triphragmium ulmarise. 104. Sphosria herbarum. OF THE FERNS AND FLOWERING PLANTS. 161 wise mould and mildew will speedily develop tliemselves, or at any rate the corollas will lose their bright tints, and the leaves become spotted and black. As most of our readers must be aware, all these plants are prepared for the herbarium, by being laid between sheets of paper and placed under pressure. The choice of paper for this purpose is by no means a matter of indifference, as the beauty of the specimens and their ultimate preserva- tion depend in a great measure on the speedy and thorough extraction of the fluids contained in their tissues.* Blotting paper is an excellent material ; but the quantity required when the gatherings are on a large scale prevents it from being ordinarily employed. On the whole, common print- ing paper may be recommended with safety ; and the cheap- ness and abundance of newspapers in the present day makes it easily attainable in large quantities. Proof, however, should be made of its powers of absorp- tion before being used; for some of the newspapers are prepared in such a manner as to prevent them from im- bibing water freely. One special point to be kept in view is, not to be sparing of the drying material, but to have so much at hand that frequent changes may be made. This is of the last im- portance, as a false economy is ruinous here. In order to dry the sheets when they are removed from the press, they must be spread out in such a manner as to expose the largest possible surface to the air. But as this occupies more space than most botanists can spare, the following plan will be found of service : it is quite as effectual, and the eye is not offended with the sight of numberless papers lying in disorder about the floor of a * An excellent paper in appearance (I have not yet had the oppor- tunity of trying it), is manufactured expressly for botanical pur- poses by E. Newman, Devonshire Street, Bishopsgate, N.E. ; and is also sold by Mr. J. Smith, 42, Rathbone Place, Oxford Street. — Ed. M 162 OF THE FERNS AND FLOWERING PLANTS. room. Four or five sheets having been laid on one another, a thread is passed through them on the folded side, some two inches from the border ; and then the two ends of the thread are tied together so as to leave a loop sufficiently large to admit of a longish rod or stick being passed through it. In this way packet after packet of damp paper is loosely fastened on the stick, and the latter is suspended horizontally in any convenient place, where there is a current of air — between the rafters of an out-house — across two chairs near a large fire — or, weather permitting, in the open air, where it will catch the rays of the sun. A few rods fitted up after this plan will allow of an immense number of sheets being dried at the same time. From the loose papers having both their sides acted on by the draught, they give up their moisture more quickly than if laid on the ground, and are not liable to be blown about by gusts of wind. The business of sewing the paper together is considerably lightened, if the end of a ball of thread is drawn, by means of a packing needle, through a great number of sheets at once, the thread being afterwards divided in lengths sufficient to bind up the packets as previously described. This saves the time, which would otherwise be wasted if the thread were cut into the required lengths before being passed through the packets. As soon as the plants are freed from the moisture on their surface, and the paper has been distributed into con- venient parcels of five or six sheets, the process of drying may be proceeded with by making alternate layers of packets and specimens until a height of some two feet has been reached. Next let the whole pile be placed between two smooth boards of the same size as the paper, and weighted with bricks, as previously recommended. . Great attention must be paid to the degree of pressure laid on ; if it be too severe the specimens will be squeezed out of all shape, whereas, if too light, the leaves, petals, and other tender parts will be shrivelled and wrinkled. It is a point on which experience and common sense must be brought to OF THE FERNS AND FLOWERING PLANTS. 163 bear, and they will be found safer guides than volumes of •advice and description. In arranging the specimen on the drying paper, the •appearance it had when living is the first thing to be thought of ; indeed, the main object in submitting it to a press at all, is that it may retain its form permanently. Before all things, therefore, care must be taken not to do violence to the plant, or force any of its members into positions which they could not possibly have held in their living state ; otherwise an ill-shapen, distorted object, which can never be restored to anything like its original form, will be the inevitable result. For the same reason no leaf or twig must be removed for the mere sake of pro ducing symmetry, or to indulge a false taste. The ono grand point to be kept in view — I cannot impress it too strongly on the young student — to which everything else must be made to yield, is the preservation of the natural habit of the plant. If that is lost sight of, his herbarium may form a pretty object in the eyes of superficial observers, but it can never be a collection of jDlants by which science will be promoted, or a knowledge of botany advanced. Of course there are times — and that not rarely — when it is actually necessary to curtail certain portions of a plant, in order that it may be prepared satisfactorily. Leaves, for instance, are constantly in the way, and must be removed to prevent them from concealing flower or fruit, or from being squeezed irregularly against the stem. Whenever, then, amputation is unavoidable, let it be performed in such a manner that there may be no mistake about it — that, in a word, anyone may see at a glance that leaves, twigs, &c. really have been removed. To this end let the leaf, supposing a leaf to interfere with the due disposition of a flower, be cut off, not quite down at its junction with the stem, but a short distance up, so as to leave a good portion of the petiole adherent to the plant ; and so of a twig, or a flower-head, or any other part, that must inevitably be sacrificed. But amputation had much m 2 164 OF THE FERNS AND FLOWERING PLANTS. better not take place at all, if it be possible to do with- out it. Should the specimen be too large to be contained within the compass of a sheet of paper, the stem must be cut half through at a convenient spot, and bent over, but at a certain angle, so that as little as possible of the upper layer shall press on the lower. Where the specimen is so long, that it is impossible to bend it so as to prevent its project- ing beyond the paper, there is no help for it but to divide it into short lengths, care being taken to mark each part, so that their true connection may be seen at once. This can be easily managed by simply varying the shape of the cut : let the two corresponding sections be rounded, notched, truncated, &c., and no mistake can arise. But I repeat, let all amputation be avoided as long as possible. As far as circumstances will permit, the different mem- bers of the specimen, I mean the leaves, stem, flowers, and so on, must not be permitted to lie directly on each other ; for, if they do, they are almost certain to cling to- gether and to become discoloured. Where it is impossible to avoid this, pieces of paper must be interposed ; any kind of paper will suffice for the leaves, stalks, and less delicate parts, but for the petals only tissue, or thin note paper, should be used : indeed, the employment of the latter during the whole course of preparation, in addition to the re- gular drying material, tends greatly to preserve their colour. Care must be taken, when arranging the order of the specimens one over the other, not to lay a thick woody plant next in succession to a thin slender specimen, as the latter will bear the impress of its stouter neighbour much to its detriment. Should it be found impossible to escape «uch an arrangement, the only remedy is to lay, not a single packet of paper as usual, but several packets between the two specimens — to heap them up, in fact, until the hand, when passed roughly over, fails to detect the protuberant stem beneath. The young botanist, in the course of his investigations, OF THE FERNS AND FLOWERING PLANTS. 165 will meet with numerous plants, belonging principally to the family Crassulaceas, such as Sedums and Sempervivums, which are so succulent and so tenacious of life, that they continue to grow after they have been laid between the sheets of drying paper. These require a special treatment of their own in order to destroy their vitality before any attempt is made to preserve them for the herbarium. To this end they are to be placed between two or three sheets of paper, the inflorescence alone projecting beyond it, and a hot iron is then passed over them. Two special pre- cautions must be taken during the operation ; one, that the flowers are not singed— the other, that the papers are changed more than once, as the plants being always of a succulent nature, a large amount of water is discharged by the heat. There are some plants the surface of which is coated with a glutinous matter, which causes them to cling to the paper, especially when under pressure : indeed, some of the foreign . Semperviva combine both these unpleasant con- tingencies, extraordinary vitality and extreme viscidity. To obviate the latter, the best plan is to sprinkle the specimen with the spores of Lycopodiiun clavatum — to be procured at most chemists under the name of f Lycopodium.’ The spores can be shaken off as soon as the plants are thoroughly dry. Delicate water plants are often difficult to deal with, as their long trailing leaves and stems are apt to get hopelessly interwoven at the moment they are taken out of their native element, and it is an almost impossible task to separate, them after they are dried. Such plants must be treated in the same way as was recommended in the case of the filamentous Alga?, viz. passing under them, while still in water, the paper, on which they are to lie. There are certain terrestrial plants, aiso of a fragile perishable nature, which must be laid at once between pieces of blotting-paper and not again disturbed until the whole process of preparation is concluded. The packets of paper, between which the specimens are 166 OF THE FERNS AND FLOWERING PLANTS. first laid, absorb their moisture so rapidly as to require frequent renewing. The oftener this can be done during the first few days the better: indeed, the student should bear in mind, that whatever trouble he gives himself in this respect will be amply rewarded by the beauty and durability of his specimens; whereas a neglect of this precaution will as surely meet with its penalty in their discoloration and ultimate destruction by mildew and the ravages of insects.
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