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ART. VII.-The Animal Kingdom described and arranged in conformity with its Organization. By the Baron Cuvier. Translated, with large additional Descriptions of all the Species hitherto named, and of many not before noticed, and with other additional matter. By E. Griffith, F.L.S., A.S., and others. Parts XXV., XXVI., and XXVII., comprising the class REPTILIA. 8vo. London: Whittaker, Treacher, and Co. 1831.
THE title which we have transcribed above, and with which we presume most of our readers are already acquainted, serves to convey a very inadequate notion indeed of the interest and value of the work to which it is affixed.
The researches which the illustrious Cuvier has so successfully prosecuted into the structure of the lower classes of the animated creation, have been acknowledged in the applause and gratitude with which his name has been crowned in every part of the civilised world. But this universal tribute, however deserved it may be, has been yielded, (so far as the bulk of mankind is concerned) almost entirely on trust, and from the credit that has been placed in the opinions of men, whose judgment and good faith, not less than their scientific attainments, fully justified such confidence. To the great mass of general readers, including those of his own nation the discoveries of Cuvier appear in the garb of a difficult and abstruse science. The graces of eloquence and imagination which carried the fame of Buffon triumphant over a thousand extravagances and mistakes, have been utterly neglected by the living philosopher, in his zeal to attain the more substantial merits of fidelity and accuracy of description; thus, governed by the maxims of a different policy from that which guided his predecessor in exploring the mysteries of nature, has Cuvier expounded the results of his vast labours with a severity of technical precision, which, at the same time that it guarantees the truth of his details, necessarily excludes the introduction of all popular attractions.
The Translator before us seems to have duly considered this peculiarity of his original, and to have founded the hope of producing a successful edition of the "Animal Kingdom" in the language of this country, only upon the conviction that he should be able to remedy what must be considered, in a certain sense, a serious objection in Cuvier's plan. To have perceived the necessity of improvement, sufficiently argued the ability to carry it into execution; and it would, therefore, be superfluous to add, that the "Animal Kingdom," enlarged and elucidated as it now appears, is one of the most entertaining registers of some of the wonders of nature, that the science of her strange operations has yet given to the world. No source of authentic knowledge, in relation to their subject, seems to have been overlooked by Mr. Griffith and his coadjutors. They manifest an intimate acquain
tance with even the most desultory of modern contributions to natural history; and from those various stores of information which immense labour and some good fortune only could enable them to command, joined to the fruits of their own personal investigations, they have contributed to the text a body of illustration, which at once varies the attractions, and materially enhances the value of the present work.
We would then, in concluding our general sketch of the English version of the Animal Kingdom, remind the reader that, in no other publication in existence, on the same subject, is there to be found a similar combination of various excellencies, as the one before us contains; a combination which, with the dry and laborious details of indispensable facts, (authenticated, however, beyond all cavil, by the cautious, patient, and sternly veracious character of him who records them), blends the charms of a happy style and the interest that belongs to the communication of surprising truths.
The class of animated beings-Reptilia-which is here treated of, furnishes a theme for endless wonder and admiration. If we can imagine to ourselves such a thing as the Author of Nature ever indulging in pastime, and that he condescended to seek amusement by a fantastic deviation from all those laws which had harmoniously prevailed in the creation of the higher orders of animals, we should certainly say that that amusement was abundantly furnished in the formation of the reptile tribes. To them life is granted upon entirely different conditions from what it has been to all other living creatures. Upon the peculiarities which characterise this class, we have the following observations of the translator:
Reptiles consist of oviparous quadrupeds and serpents. To the first, the name of reptile is as suitable as to the last for though they have feet, they make little use of them, except in creeping, and their belly almost always touches the ground. Tortoises, lizards, frogs, toads, and salamanders, afford sufficient proof of this. Though the three last-mentioned genera live in the water, and swim there with facility, they also live on land very well. For this reason some naturalists have considered them as true amphibia. But, in fact, for an animal to be amphibious, in the strictest acceptation of the term, it is necessary that it should possess the power of respiring under the water like fishes, and on the earth like mannone, therefore, of these animals are true amphibia, except, perhaps, the siren and the proteus, which possess both lungs in the chest, and external gills. Frogs, toads, and salamanders, when in the tadpole state, are provided only with gills, which respire the water, and, accordingly, in this tadpole state, they cannot live out of the liquid element. When they become perfect animals the gills disappear, and they breathe by lungs; consequently, they are then obliged to respire the air, and would perish by suffocation under water, were they forced to remain submerged for too long a period of time.'-p. 22.
In their bony system, in the arrangement of their brain, in the number of their senses, and in the structure with which they are
endowed for breathing and digestion, the reptiles bear a striking analogy to the superior classes of animals; but there the resemblance stops. The blood, which in all other animals must receive in the lungs a renewed supply of oxygen, presents itself very partially in the lungs of reptiles; and hence we find, in general, that life in their bodies is exceedingly languid, and the surface of the bodies themselves remarkably cold.
They seem, for the most part, to vegetate rather than live; to be insensible of a wound, and even scarcely to discover any considerable degree of anguish when cut in pieces. Their organization very speedily renews many parts, such as the tail or toes, when they have been removed. As these animals have but very little cerebellum in proportion to their size, and a brain composed of but six small tubercles, their existence is not so absolutely concentrated in their head as ours. It seems rather to be attached to their spinal marrow, and to be more generally disseminated throughout their body. A tortoise has been known to live for eighteen days after the brain was removed, still walking about, but groping its way, for its eyes were closed, and the power of vision lost in consequence of the cutting of the optic nerves. A salamander has lived several months although decapitated by means of a ligature fastened tightly round the neck. The heart of a viper, when plucked out, will beat and contract on being pricked, for the space of forty hours.—pp. 23-24.
The system of respiration in reptiles is the principal character which separates them from all other animals, and exercises the most powerful influence over all the parts of their organization. In organized bodies there are certain general modes of conformation which necessitate a multitude of particular conformations. Thus, for example, the animal whose stomach is found to digest flesh, must be furnished with teeth proper for tearing it, robust muscles for vanquishing his prey, agile limbs for overtaking it, &c. In like manner, the external organs of every being are all in relation to the wants of the internal organs; the latter must, therefore, be investigated, if we want to ascertain the cause which determines the conformation of the former.'-pp. 24-25.
There is one very singular property in the reptile races, which has been noticed in the text. This is the power of reproducing certain parts, such as the tail, feet, &c. when they have been lost. This fact is particularly demonstrated in salamanders and lizards, and was known as long ago as the time of Aristotle. They are also, as has before been hinted, remarkable for their extreme tenacity of life, and the long duration of their fibrous irritability after life is extinguished.
'The weakness of respiration diminishes the activity of the nutritive system in reptiles, because the one is always in relation with the other. Accordingly, these animals eat but little, and digest slowly.
The small quantity which reptiles eat, is another reason for the slowness of their growth, and the length of their existence; and the same character is also connected with the inactivity of their senses. Their organs of sensation seem scarcely developed. Their touch is very obtuse, in consequence of the density and hardness of their skin. Their sense of taste cannot be otherwise than dull, because the tongue is either cartila
ginous, or covered with a thick and viscous humour. The smallness of the organs of smelling, indicates the weakness of that sense. That of hearing appears to be less imperfect, though its organ in reptiles is destitute of many useful parts, such as the cochlea, the conch, and the meatus externus. Even the tympanum is usually covered with skin, scales, or muscles. Sight is the most perfect sense in reptiles. They have, for the most part, very large eyes, a contractile pupil, like that of cats, (especially the geckos, which appear to see clearly by night,) and a nictitating membrane, the same as in birds. This indicates a great sensibility in this organ in these two classes of animals, and the necessity under which they labour of having the intensity of the light moderated in its action on their eyes. Nevertheless, the CECILIA, a genus of serpents approaching the batracians, have excessively small eyes concealed under the skin. The brain of reptiles is remarkably small, and does not even completely fill the cavity of the cranium, though that is far from being capacious. pp. 27-28.
It is at the period of reproduction that the voices of reptiles are chiefly to be heard, which vary very considerably. The crocodiles, but more particularly the caymans of America, are said to howl loudly. The hissing of serpents and the croaking of frogs are well known. A traveller towards the desert shores of the Caspian and the Volga, would imagine that he heard of a sudden, in the evening, a joyous assembly of men and women laughing heartily. He approaches; the inextinguishable laughter redoubles among the rocks, and, to his astonishment, he finds that it proceeds from an assembly of enormous black toads celebrating their nuptial orgies. Certain species of America imitate the sound of a funeral bell tolling during the night, and others the rattling noise of cymbals.
Though reptiles never sit upon their eggs, it does not appear that the sentiment of maternity is altogether non-existent among these animals. There are serpents (and those are particularly the venomous species) which retain their eggs in their oviducts longer than other animals of their kind. These eggs disclose within, and the young ones come out alive. These animals produce in smaller number than those reptiles which lay their eggs. It is said that the female crocodile lays its eggs on a bed
of rushes and sand, and that she covers them with a second and a third similar bed, with other layers of eggs, to conceal them from the watchful ichneumon. The serpents heap up theirs in some hole exposed to the sun, Small lizards have been observed carefully carrying their eggs in the mouth to warmer places, more favourable for the seclusion of the young. But the young, once disclosed, have nothing more to expect from the mother. She has no milk to offer them-she takes no care to provide them with nourishment of any kind; still, even if a great number of these young should perish, there is no fear of the extinction of the species, nature having made a sufficient provision against that in the excess of their fecundity.'-pp. 42-43.
The class of Reptiles being divided into four orders, each is described, at length, in succession. The first order, the Chelonia, or the Tortoise, includes the Turtle, of the varieties of which we have some very curious information from the pen of Mr. Griffith.
It is in the month of April that the females deposit their eggs in a dry place on the shore. They first of all, without ever being accompanied by the males, seek out a convenient situation, quitting the water after many precautions after the setting of the sun, but return immediately to the sea on the slightest disturbance. If this is not the case, they proceed above the line of the highest tide, excavate the sand with their fins, and, after having made a hole of about two feet deep and two wide, formed like reversed cone, they deposit their eggs there, sometimes to the number of one hundred in a single night, During this labour nothing can disturb. them or distract their attention. At such times, they are taken with great
In this manner, they lay three successive sets of eggs-an interval of fourteen days or three weeks elapsing between each set. They return to the sea, after having covered their eggs with sand.
We are told by Père Labat, that on the coast of Africa a single one of these tortoises will produce two hundred and fifty eggs, and even more.
The young are excluded generally in about three weeks, though some little variation will take place according to latitude, and the temperature of the atmosphere. The accounts of authors, however, on this subject, cannot be implicitly relied on, as they abound in contradictions, though the above may be considered the average time.
The eggs are round, two or three inches in diameter, and enveloped in a soft membrane, not unlike moistened parchment. Their albuminous part does not coagulate in the fire, but the yoke hardens very well.
These eggs are excellent eating, and in great estimation.
With the very young turtles, the carapace is covered with a white and transparent skin, which grows brown by degrees, forms transverse wrinkles, then thickens, and finally is divided into scaly plates.
'Dampier has remarked, that towards the season of laying, the greater number of these turtles remove for two or three months from the latitudes where they habitually reside. They proceed to deposit their eggs at some distance from their usual domicile, and then abandon them. In this voyage the male follows the female, and does not quit her until their return. It is believed that during the whole time of their absence they eat nothing; it is certain they are extremely lean when they do return, especially the male. The same traveller adds, that they are accompanied in their route by sharks and an infinite number of other fishes.
The places most remarkable for the deposition of eggs by the testudo mydas, are the Alligator Islands, in the sea of the Antilles, and that of Ascension, in the middle of the Equinoxial Atlantic Ocean. They arrive at the former from the end of April to the month of September, and none of them can have travelled less than forty or a hundred leagues, for such is the distance from their nearest points of departure, which are the little isles southward of Cuba. Those which proceed to Ascension Island cannot have travelled less than three hundred leagues, whether they come from Africa or America.
'An innumerable quantity of these turtles are found in the channels between the Gallapago Islands and the Equinoxial Ocean. They proceed to the coasts of America to deposit their eggs—a distance, at the least, of one hundred and forty leagues.
In consequence of all this we may believe, that the same instinct