the ova, very similar to the masses of frog-spawn in ditches.'

curiously incurvated or notched, of sharks and rayfishes; in some of which these organs are so arranged as if to render them incapable of inflicting an injury; and yet, by some peculiarity of action, these fishes are formidable enemies to those who venture to attack them. Sticklebacks, (Gasterostei,) also, and probably the Scad, (Caranx trachurus,) employ their spines, and even their lateral plates, in lacerating such of the scaly tribe as seek to injure them."-p. 73

"Some of these nests are formed in pools, and are consequently always in water; others are frequently to be found between tidemarks, in situations where they hang dry for several hours in the day; but whether in the water, or liable to hang dry, they are always watched by the adult animal. On one occasion I repeatedly visited one every day or three weeks, and invariably found it guarded. On several occasions I laid the eggs bare, by removing a portion of the nest, but, when this was We have frequently observed the same means discovered, great exertions were instantly made to of defence resorted to by the fresh-water perch, re-cover them. By the mouth of the fish the edges which, lying temptingly near the surface of the of the opening were again drawn together, and other portions torn from their attachments, and brought water, as if to invite attention, will erect the over the orifice, till the ova were again hid from spiny rays of its dorsal fin, and severely lacerate view. And as great force was sometimes neces- the hand of any one incautiously attempting to sary to effect this, the fish would thrust its snout seize it.

into the nest as far as the eyes, and then jerk back- We now enter upon the consideration of a new wards till the object was effected. While thus en-order of beings, retaining no trace of the vertebral gaged it would suffer itself to be taken in the hand, column characteristic of the four great groups we but repelled any attack made on the nest, and quitted not its post so long as I remained; and to those nests that were left dry between tide-marks, the guardian fish always returned with the returning tide, nor did they quit their post to any great distance, till again carried away by the receding tide.'' -p. 254.

have just been speaking of, and which, instead of possessing an internal framework of bones on which their bodies are modelled, are cased in a horny or membranous suit of armor, which serves as the external support for their muscles, as well as a protection to the internal tissues and organs. The same gentleman states that he has observed Insects furnish some of the most striking instances another kind of nest which showed "considerably of instinct that can be found in the whole animal less skill in the fabrication, but more perseverance kingdom; though Mr. Couch somewhat unaccountand continued energy. These were formed of the ably dismisses them by merely quoting a few common coralline, forced into a cavity or crevice descriptions of extraordinary migrations of what he

of a rock but as the coralline used in the construction of these last-described nests is sometimes not to be found within one or two hundred feet, it must be gradually gathered and brought from a distance; and as the quantity is large it shows an intelligence and perseverance truly wonderful."

After these interesting particulars of the existence of such a habit in a class of animals where least it could have been suspected to exist, it is almost unnecessary to adduce any further proofs of the presence of the particular faculty we claim for them, especially as Mr. Couch himself admits an "instinctive care of their progeny in fishes." We may, however, be permitted to mention the peculiar means of defence provided in the electric eel, and the torpedo, as well as the armature of spines furnished with the same object to many

66 terms a class of animals, in which the modes of proceeding, and the motives which lead to them, are so obscure as to preclude any attempt at explanation." Many of the proceedings and motives of insects are doubtless obscure; but far more are so clearly expressed that "he who runs may read." Some insects, for example, under the impulse of providing for that offspring which the parents are never to behold, after constructing a suitable habitation in which to deposit their eggs, with an admirable instinct are actually at great pains to furnish the larder with such food as the young one will stand in need of on its exclusion from the egg, and so placed as to be readily accessible the moment it is required. Nor is the nature of this food less a proof of instinct than the fact of its being stored up in some cases it is of a vegetable nature; in others, a living caterpillar, belonging to some other species, is seized by the parent "The torpedo, (T. nobiliana and its congeners,) insect, rendered insensible, but not killed, (which conscious of being without the spines which consti- would defeat the object,) by a puncture from the tute the means of defence of most of the natural sting of its captor, and conveyed to the nest family to which it belongs, when only just excluded wherein the egg is to be deposited. Every one from the egg, displays the will to exert the same [electric] power; and none of the creatures fur- has observed the caterpillar of the common cabbage nished with it are known to resort to any other. It butterfly apparently brooding upon a heap of yellow is a curious circumstance, that several species of eggs. This affords a beautiful illustration of fishes which possess a formidable arrangement of instinct on the part of a small black fly which spines, are yet furnished with them in such situa- deposits its eggs within the body of the living cattions, and with the points so directed, as to appear erpillar. The young grubs, when evolved from the least likely to be effective against an adversary; the egg, feed upon the internal tissues of their vicand yet, when brought into operation, some sudden

other fishes.

motion shows how well acquainted they are with tim, instinctively avoiding, however, to attack any the uses of which they are susceptible. This is vital part, since the premature death of the caterwell exemplified in the spines, in many instances pillar would ensure their own destruction. At

ength the time approaches for the parasites to take upon themselves a new condition of insect life, namely, that which immediately precedes their perfect winged condition; at the same period, the caterpillar infested by them instinctively seeks out some spot wherein it also may pass through the corresponding state of inactivity, preliminary to its appearance as a winged denizen of the air. No sooner, however, has it attached itself, than the grubs contained in its body make their exit through the skin; each spins its own little cocoon of yellow silk, wherein to await its final change. These cocoons are collected together beneath the body of the caterpillar, which, being now in too exhausted a condition to pass into the chrysalis state, speedily dies, while, after a short period, the parasites break from their cocoons and become perfect insects, in their turn seeking for new victims.

the name. Among the higher orders of this group we find the cuttle-fish, the Argonauta or paper nautilus, and the pearly nautilus, each of which presents us with an instance of instinct acting for the preservation or the convenience of the animal.

From a very early period, naturalists have been aware of the power exercised by the cuttle-fish, when in danger, of expelling a black fluid, in sufficient quantity, when mingled with the surrounding water, to hide the animal from its pursuers. This fluid is secreted by a singular organ connected with the intestine; the animal is, moreover, furnished with parrot-like jaws, put in motion by powerful muscles, well-developed salivary glands, several stomachs, and a large liver; all indicating not only that the instinctive feeling of hunger is habitually experienced, but that the means of allaying that feeling are amply provided; while the apparatus connected with the secretion and expulsion of the inky fluid is expressly formed to enable an otherwise defenceless animal to exercise its instinctive demand for self-preservation in the manner most consistent with its mode of life and organization.

Whoever has paid attention to the manners of insects, will be at no loss to understand many of their "modes of proceeding" or "the motives which lead to them." The intention of the silken cord by which the caterpillar of many butterflies secures itself to a perpendicular wall previously to becoming a chrysalis, cannot be misunderstood. The interesting poetical fiction connected with Nor can we fail to understand the intention of the the argonaut or paper nautilus, wherein it is reprecoat of armor formed around itself of small stones, sented as sailing on the surface of the sea, its frashells, or bits of stick, by the larva of the Phry- gile shell forming the hull of its vessel, the two ganea; the use of the paper manufactured by the expanded membranous arms being erected and actwasp; of the waxen cells and store of honey pro-ing as sails, while the six tapering arms were used vided by the bee; of the covering of down stripped from its own body by the female of the gypsy moth, with which its mass of eggs is protected from the severity of winter; these are all equally easy of comprehension; and no one at all acquainted with these interesting creatures and their habits will venture to deny them the possession of instinct, nor, in some cases, of a certain amount of reason either. For, as Mr. Couch, in the main accurately observes, though with a slight confusion of terms at the outset,—

"The simplest instinct will vary its proceedings according to circumstances; and the smallest glimmering of reason will direct it to modify these proceedings according to situation, and as they may best lead to the desired result. In many creatures of the land this variation is of common occurrence, and is not only directed according to a change of circumstances, but sometimes seems to be under no better influence than caprice. The daubers, a genus of North American wasps, to save themselves the labor of building a cell, have been known to make use of a small bottle, closing the orifice with clay; and the mason bees, (Osmia,) which usually deposit their eggs in holes dug by themselves in walls or sand-banks, will embrace the opportunity of saving themselves labor, by employing for the same purpose the empty shell of a snail."-p. 258.

The next grand group in a descending order, comprises the molluscous and the vermiform animals, under the general name of mollusks. Here we lose both the internal bony skeleton of the vertebrated animals, and the external crustaceous covering of the Articulata, the typical members of the group being preeminently soft-bodied; whence

as oars, has, for ages, rendered that animal an object of interest; and notwithstanding that these particulars have been proved fictitious, recent researches into its true history have shown the mollusk to be no less deserving consideration from its every-day actions, than from the exploded functions poetically ascribed to it. From the excessive thinness of the beautiful shell, to which, by the way, the animal has no muscular attachment, and its extreme fragility, it is constantly liable to fracture by being tossed about at the mercy of the waves. When this happens, and it is no unusual occurrence, the animal instinctively repairs the fracture by a new deposition of shelly matter to the broken portion, by means of the membranous mantle. This circumstance, observed in a number of argonauts kept in confinement in an open cage sunk in the sea in the Bay of Messina, by Madame Power, removed the doubts of naturalists as to the animal being really the architect of its own habitation; since the regular increase in the size of the shell to correspond with the growth of the animal was witnessed, as well as the power of repairing the shell when broken either intentionally or accidentally.

The shell of the Argonauta contains but one spiral cavity, into which the animal can wholly withdraw itself. When by the growth of its body the animal finds its habitation too small for it, like other mollusks it has the power of increasing its dimensions by successive additions of shelly matter to the outer edge. In an allied member of this family, however, the enlargement of the shell is effected by a much more elaborate process. Ex

ternally, the shell of the pearly nautilus has noth- the star-fishes, (Asteriada,) whose beauty and sym. ing more remarkable in its appearance than that metry, as Professor Forbes well observes, have of the common garden snail; but a longitudinal" attracted the attention of such observers of nasection shows it to be internally divided into a number of chambers by transverse partitions of shelly matter, the outer chamber being the largest; and this contains the body of the animal, the remainder being unoccupied. The animal maintains a connection with all the chambers by means of a membranous tube, called a siphuncle, which passes down through a perforation near the centre of each partition. When it becomes necessary to enlarge the shell to accommodate it to the growth of the animal, the latter not only adds fresh layers of shelly matter to the outer edge, so as to enlarge the chamber in which it resides, but at the same time constructs a new partition across the inner part, below its body, so as to form an additional chamber. So that the number of chambers in the shell of the pearly nautilus varies according to the age of the individual.

ture as dwelt by the sea-side from a very early period." These members of the Echinodermata are adduced by Mr. Couch, as examples exhibiting the earliest manifestations of a true nervous system; and these animals, he continues, "though seemingly very inert, and destitute of intelligence, display some sagacity in the discovery and choice of food, as well as in the manner of seeking it; and are liable to variations of habit in the differ ent seasons of the year." At the extremity of each ray in the true star-fishes is a small red point, connected with the nervous cord of the ray, and protected by a circle of spines, capable of being expanded or closed at the will of the animal; these points are believed to be organs of vision, which belief is strengthened by its being observed that the star-fishes take cognizance of food placed at a short distance from them. In their movements from place to place they seem to avoid obstacles lying in their path; and from all observation they doubtless perform various actions under the influence of the instinctive impulse.

Among the Echinodermata, progression is effected by means of suckers and spines; the starfishes or Asteriada employ the former exclusively; the sea-urchins, or Echinidæ, progress by means of the joint action of their suckers and spines. Professor Forbes observes, that "many sea-urchins, such as live on hard surfaces, moor themselves also by means of the suckers, and thus adhere very firmly to the rocks," and con tinues :

This habit of forming chambers in the shelly covering of the mollusks, is not confined to the higher members of the family; but is also practised, though from a different cause, by some of the more simply organized individuals. In the case of the water-clam, (Spondylus varius,) a bivalve nearly allied to the common oyster, and which, like the oyster, is attached by the outer surface of the lower valve of its shell to some extraneous body, when the animal happens to be developed beneath the overhanging ledge of a coral reef, or in a situation where, having no power of locomotion, it would run the risk of being overgrown by the coral, it resorts to the expedient of carrying forward its dwelling-chamber by a series of new formations of shelly matter, noderms provided with these suckers, they serve so as always to keep its respiratory and nutrative not merely for progression; the lower we descend apparatus on a level with the surrounding zoo- in the scale of animal nature, (and equally in the phytes. A longitudinal section of these shells vegetable kingdom,) the more functions do we find exhibits sometimes as many as fourteen such cham- performed by one organ. But observe a living bers, separated from each other by stout and reg-star-fish, or a living Holothuria, and see what ef ularly formed partitions. The common oyster, weak-looking tubes are. fective organs of progression these soft, flexible, I have seen an Echinus when, from a deficiency of food, its body has miliaris, a Spatangus purpureus, and an Amphishrunk so as no longer to fill the interior of the dotus roseus, all walk along the bottom and up the shell, will form a new layer of nacre, and thus sides of a dish of salt water by means of their inadapt the cavity to its changed condition by adding ferior tentacula; and the first mentioned anchored a chamber in the rear of its diminished body. itself by extending and bending its superior suckers, so as to reach the bottom of the dish."-" History of British Starfishes," p. 144.

In the next grand group of animated nature, the Radiata, we reach the lowest types of organization, among which, if at any part of the scale of being, we should be most warranted in looking for evidences of the entire absence of animal instinct.

A few examples of actions evidently performed under the impulse of that innate sensation, which, independently of instruction, insures both the preservation of the individual and the continuance of the species, will however demonstrate that in its proper sense, these lowly beings, equally with man, are subject to the promptings of instinct.

Beginning with the order Echinodermata, or those radiated animals whose integument is covered with spines or prickles, we find among them

"There can be no doubt that in all the Echi

The passage above quoted will show by what means the common sea-urchin, or sea-egg, (Echi nus sphæra,) is enabled to perform a not unusual feat, related by Mr. Couch, who says that this animal, "though apparently destitute of every sense or possibility of regarding external objects by sight or hearing, will travel up the rods of a crab-pot, enter the opening, descend within, mount again to the bait, and select the particular one that pleases it best ;" this is almost an act of

reason.

Among the Crustacea, there is a family of crabs, named Paguridæ, or hermit-crabs, which, instead of being entirely cased in armor, as are

the other members of the class, have merely the of these little animals leads them to build with claws enclosed in the usual calcareous envelope, the thorax being less firm, and the abdomen quite naked. Many of these crabs defend their soft tails by taking up their abode in empty univalve shells, to the interior of which they attach themselves by a sucker placed at the extremity of the tail, and only quit their habitation when the increase in size of their own bodies renders it necessary to look out for a new domicile.

the greatest rapidity to the windward, or most exposed side of their edifice, leaving the side least exposed to the action of the waves to be last completed. Their labors are also instinctively confined to low-water-mark, below which they do not build. Mr. Darwin has recorded in his journal much valuable information respecting the little architects and their wonderful structures. Among Even among the Infusoria, the thoughtful obthe Radiata is a species of very simple organiza-server must recognize the influence of instinct tion, which resorts to a similar expedient for the when he views their varied movements and the protection of its soft body, with an additional dis- elaborate apparatus with which many of these play of ingenuity not evinced by the crab. Pro- minute creatures are provided for the purpose of fessor Forbes thus describes the habit of this securing their food. In the words of Dr. Mancreature, which he has named the Shell-bearing tell,— Sipunculus (Sipunculus Bernhardus) :—

"No organs of progressive motion, similar to those of beasts, birds, or fishes, are observable in these beings; yet they traverse the water with rapidity, without the aid of limbs or fins; and though many species are destitute of eyes, yet all possess an accurate perception of the presence of other bodies, and pursue and capture their prey with unerring purpose."

"The species [of the genus Sipunculus] bury in sand, or in the crevices of rocks, or, as is the custom of the curious animal before us, adopt the shells of dead univalve Testacea for a house and home, after the manner of the hermit-crab. The Sipunculus would appear, however, to be of a less changeable disposition of mind and body than its crustacean analogue, and when once securely As has already been explained in this Review,* housed in a shell, to make that its permanent these various motions are performed by means of habitation. Whether the egg is originally de-minute hair-like filaments, termed cilia, which posited in the future habitation of the animal, by some wonderful instinct, or is only developed cover and fringe the bodies of the Infusoria; and when lodged by the waters in such a locality, or we quote an accurate and spirited description of whether the parent Sipunculus bequeathes the their movements from Dr. Carpenter's "Zoology." chosen lodging of its caudal termination to its eldest born, and so on from generation to generation, a veritable entailed property, we know not at present; but the inquiry is a most interesting one, and well worth the attention of the experimental zoologist. The Sipunculus is not, however, content with the habitation built for it by its molluscan predecessor; it exercises its own architectural ingenuity, and secures the entrance of its shell by a plaster-work of sand, leaving a round hole in the centre sufficiently large to admit of the protrusion of its trunk, which it sends out to a great length, and moves about in all directions with great facility."-" British Star-fishes," p. 252.

"These movements are extremely various in their character in different species; and when a number of dissimilar forms are assembled in one drop of water, the spectacle is most entertaining. Some propel themselves directly forwards, with a velocity which appears (when thus highly magnified) like that of an arrow, so that the eye can scarcely follow their movement; whilst others drag their bodies slowly along, like the leech. Some make a fixed point of some portion of the body, and revolve around it with great rapidity; whilst others scarcely present any appearance of animal motion. Some move forwards by an uniform series of gentle undulations or vibrations; whilst others seem to perform consecutive leaps, of no small exshort, there is no kind of movement which is not tent compared with the size of their bodies. In practised by these animalcules. They have evidently the power of steering clear of obstacles in their course, and of avoiding each other when swimming in close proximity. By what kind of sensibility the wonderful precision and accuracy of their movements is guided, is yet very doubtful."

Professor Forbes figures one of these animals, which had taken up its quarters in an empty per iwinkle-shell. Nothing, we think, can more clearly demonstrate the presence of an instinctive impulse towards self-preservation in this lowly animal than the proceedings above detailed. Allow that the Pagurus is impelled by instinct to choose an empty shell for the protection of its tender abdomen, and the same motive must be The mode in which these cilia subserve the purgranted to actuate the Sipunculus in performing pose of procuring food may best be understood by a similar action for a like purpose. Nor in either studying the habits of the common wheel animalcase can we see any other motive than that which cule, (Rotifer vulgaris,) which, from its activity, directs the beaver in the construction of the hab- and the variety of its movements, is one of the itation which is to serve as a shelter for himself most interesting of microscopic objects. This speand his progeny. cies, at its anterior extremity, is furnished with The labors of the coral-polypes afford very strik-two sets of cilia, disposed in circles, forming what ing examples of the exercise of instinct, while they exhibit the wonderful results of the combined efforts of numerous minute animals, which, individually, are comparatively powerless, and their organization very simple. In the formation of the immense coral reefs and islands, the natural instinct Revelations." 23

CXCVII.

LIVING AGE.

VOL. XVI.

are termed the wheels; these are capable of being folded up and retracted within the body of the creature. When desirous of procuring food, the Rotifer fixes itself by the extremity of its telescope*No. 90, October, 1846. "The Microscope and its

like tail, and protrudes the cilia from the opposite and by the disturbance of those which may be extremity; by the vibration of the cilia, which is floating in the surrounding fluid ;" and he concontinued or suspended at the will of the animal, tinues:-"It is impossible to assign a cause for the appearance of a perfect rotation is produced, this movement; no cilia have been discovered in which has the effect of creating rapid currents in any part of the adult animal; and the tissues are the surrounding fluid. A sort of whirlpool is altogether possessed of so little contractility, that caused by each wheel, and this brings towards the it is difficult to suppose the fluid propelled through mouth minute animalcules and other bodies float- the tubes by any mechanical influence on their ing in its neighborhood, many of which are drawn part." As this circulation of fluid ceases when into the gullet, while others are rejected and car- the sponge is dead, we are inclined to view it as ried off by a return current. This proceeding has the instinctive means, the blind impulse, whereby been likened by Spallanzani to that of a whale, the nutrition and growth of the organism are inwhich, having driven a shoal of herrings into a sured. From the water thus continually passing bay, by repeated blows of his tail, produces a whirl- through its tissue, the sponge secretes its own pool of considerable extent and rapidity of motion, peculiar organic texture, as well as the spicula of whereby the herrings are projected into the mouth earthy matter, as carbonate of lime and silex, disof their pursuer. If this proceeding on the part posed among its tissues. But the passage of the of the whale be the result of instinct, so must it water is of quite a different character from the also be considered when practised by the animal-ascent and descent of the sap in plants; since, in cule; the object being the same, and the means the latter, the fluid absorbed by the spongioles of resorted to for securing it similar.

the roots becomes gradually elaborated by the It would seem that both this beautiful creature vital action of the plant into the various substances and its near ally, Hydatina senta, together with requisite for its nutrition and increase, all that some at least of the polypes, enjoy a considerable escapes passing off by perspiration from the leaves; power of selection in regard to their food. A while the sponge would appear merely to select species of the latter family, Bowerbankia densa, certain substances from the water in its passage, about half an inch in length when fully expanded, the greater portion being rejected, and expelled by is so transparent, that the whole of its structure the large orifices; the action being somewhat and the actions of its organs may be seen through analogous to the entering and returning currents in its integuments. Like the two Infusoria, the polyp the Infusoria, with this difference, that in the latter attaches itself by its lower extremity, and protrudes the cilia are obviously the motive organs. its tentacula, which, like the cilia of the former, Other organisms of a still more doubtful descripare ranged round its mouth, and seem to be com- tion than the sponges are placed in this division of pletely under the control of the individual; these, the animal kingdom by some naturalists, though it when put in motion, produce a current of water, seems now to be the prevalent disposition to conwhich brings the various substances floating in it sider them as of vegetable nature. Such are many to the entrance of the mouth. As in the Infusoria, of those beings long known as Confervas, and other some of these matters are received into the gizzard, plants of a very low organization. The chemical while others are rejected; the gizzard, as in them, constituents of these, the lowest members of the is furnished with teeth, which triturate the food two kingdoms, are so nearly the same, that it is before it passes into the stomach; all these actions only by the detection of a small quantity of starch present a curious analogy between animals belong-in some of them that they can be recognized as ing to two classes of different degrees of organiza-plants; and even among these, the action of one tion; and it is probable, that but for the extreme of the most powerful animal instincts has been obminuteness of many of the other Infusoria, numer-served; for in several of those now looked upon ous other actions would be observed, which in as plants, a kind of conjugation has been witnessed, combination with those already recorded, would leading to the production of a new individual, by remove all doubt as to their being as certainly under which the race is continued; and animal motions the influence of instinct as animals of a much higher are by no means of unfrequent occurrence. So grade. that, even in these doubtful beings, instinct evidently holds its sway, directing them to the attainment of certain ends absolutely necessary to their well-being.

The lowest position in the scale of animated beings seems to be occupied by organisms which many naturalists have been rather inclined to place with plants; amongst these, the most conspicuous In conclusion, we would briefly state our conare the sponges and their allies. When studied viction, founded upon observation of the infinitely in a living state, a constant and rapid circulation varied habits of animals, that every integral portion of water through their tissue is almost the only of the animal kingdom, from the highest to the action by which the existence of life in these sim- lowest, has, according to its requirements, been ple beings is manifested. The water enters by furnished by its beneficent Creator with such a the smaller orifices, traverses the smaller cavities measure of an innate impulsive power as is suffiof the spongy structure, and is eventually expelled cient to ensure the due performance of such actions by the larger orifices or vents. "This stream," as are necessary for the preservation of its own says Dr. Carpenter, "is made apparent by the individual existence and the continuance of its kind. movement of the minute particles contained in it, That these instincts, strictly so called-these im