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lame, the aged, and the supernumeraries, are consigned to speedy death; and while each suffering individual is soon relieved from pain, it contributes its enfeebled carcass to the support of its carnivorous benefactor, and leaves more room for the comfortable existence of the healthy survivors of its own species.
The same " police of Nature," which is thus beneficial to the great family of the inhabitants of the land, is established with equal advantage among the tenants of the sea. Of these also, there is one large division that lives on vegetables, and supplies the basis of food to the other division that is carnivorous. Here again we see, that in the absence of carnivora, the uncontrolled herbivora would multiply indefinitely, until the lack of food brought them also to the verge of starvation; and the sea would be crowded with creatures under the endurance of universal pain from hunger, while death by famine would be the termination of ill-fed and miserable lives.
The appointment of death by the agency of carnivora, as the ordinary termination of animal existence, appears therefore in its main results to be a dispensation of benevolence; it deducts much from the aggregate amount of the pain of universal death; it abridges, and almost annihilates, throughout the brute creation, the misery of disease, and accidental injuries, and lingering decay; and imposes such salutary restraint upon excessive increase of numbers, that the supply of food maintains perpetually a due ratio to the demand. The result is, that the surface of the land and depths of the waters are ever crowded with myriads of animated beings, the pleasures of whose life are co-extensive with its duration; and which throughout the little day of existence that is allotted to them, fulfil with joy the functions for which they were created. Life to each individual is a scene of continued feasting, in a region of plenty; and when unexpected death arrests its course, it repays with small interest the large debt, which it has contracted to the common fund of animal nutrition, from whence the materials of its body have been derived. Thus the great drama of universal life is perpetually sustained; and though the individual actors undergo continual change, the same parts are ever filled by another and another generation; renewing the face of the earth, and the bosom of the deep, with endless successions of life and happiness.
Proofs of design in the Structure of Fossil Vertebrated Animals.
FOSSIL MAMMALIA. D1NOTHERIUM.
Enough has, I trust, been stated in the preceding chapter, to show the paramount importance of appealing to organic remains, in illustration of that branch of physico-theology with which we are at present occupied.
The structure of the greater number, even of the earliest fossil Mammalia, differs in so few essential points from that of the living representatives of their 'respective Orders, that I forbear to enter on details which would indeed abound with evidences of creative design, but would offer little that is not equally discoverable in the anatomy of existing species. I shall, therefore, limit my observations to two extinct genera, which are perhaps the most remarkable of all fossil Mammalia, for size and unexampled peculiarities of anatomical construction; the first of these, the Dinothe
Hum, having been the largest of terrestrial Mammalia;* and the second, the Megatherium, presenting greater deviations from ordinary animal forms, than occur in any other species, either of recent or fossil quadrupeds.
It has been already stated, in our account of the Mammalia of the Miocene period of the tertiary series, that the most abundant remains of the Dinotherium are found at Epplesheim, in the province of Hesse Darmstadt, and are described, in a work now in process of publication, by Professor Kaup. Fragments of the same genus are mentioned by Cuvier, as occurring in several parts of France, and in Bavaria and Austria.
The form of the molar teeth of the Dinotherium, (PI. 2. C. Fig. 3,) so nearly resembles that of the Tapirs* that Cuvier at first referred them to a gigantic species of this genus. Professor Kaup has since placed this animal in the new genus Dinotherium, holding an intermediate place between the Tapir and the Mastodon, and supplying another important extinct link in the great family of Pachydermata. The largest species of this genus, D. Giganteum, is calculated, both by Cuvier and Kaup, to have attained the extraordinary length of eighteen feet. The most remarkable , bone of the body yet found is the shoulder-blade, the form of which more nearly resembles that of a Mole than of any other animal, and seems to indicate a peculiar adaptation of the fore leg to the purposes of digging, an indication which is corroborated by the remarkable structure of the lower jaw.
The lower jaws of two species of Dinotherium, figured in Plate 2. C. Figs. 1. 2. exhibit peculiarities in the disposition of the tusks, such as are found in no other living or fossil animal.
* The Author has recently been informed by Professor Kaup, of Darmstadt, that an entire head of this animal has been discovered at Epplesheim,. measuring more than a yard in length, and as much in breadth, and that he is preparing a description and figures of this head for immediate publication.
The form of the molar teeth, PI. 2. C. Fig. 3, approaches, as we have stated, most nearly to that of the molar teeth in Tapirs; but a remarkable deviation from the character of Tapirs, as well as of every other quadruped, consists in the presence of two enormous tusks, placed at the anterior extremity of the lower jaw, and curved downwards, like the tusks in the upper jaw of the Walrus. (PI. 2. C. 1. 2.)
I shall confine my present remarks to this peculiarity in the position of the tusks, and endeavour to show how far these organs illustrate the habits of the extinct animals in which they are found. It is mechanically impossible that a lower jaw, nearly four feet long, loaded with such heavy tusks at its extremity, could have been otherwise than cumbrous and inconvenient to a. quadruped living on dry land. No such disadvantage would have attended this structure in a large animal destined to live in water; and the aquatic habits of the family of Tapirs, to which the Dinotherium was most nearly allied, render it probable that, like them, if. was an inhabitant of fresh-water lakes and rivers. To an animal of such habits, the weight of the tusks sustained in water would have been no source of inconvenience; and, if we suppose them to have been employed, as instruments for raking and grubbing up by the roots large aquatic vegetables from the bottom, they would, under such service, combine the mechanical powers of the pick-axe with those of the horse-harrow of modern husbandry. The weight of the head, placed above these downward tusks, would add to their efficiency for the service here supposed, as the power of the harrow is increased by being loaded.
The tusks of the Dinotherium may also have been applied with mechanical advantage to hook the head of the animal to the bank, with the nostrils sustained above the water, so as to breathe securely during sleep, whilst the body remained floating, at perfect ease, beneath the surface: the animal might thus repose, moored to the margin of a lake or river, without the slightest muscular exertion, the weight of the head and body tending to fix and keep the tusks fast anchored in the substance of the bank; as the weight of the body of a sleeping bird keeps the claws clasped firmly around its perch. These tusks might have been farther used, like those in the upper jaw of the Walrus, to assist in dragging the body out of the water; and also as formidable instruments of defence.
The structure of the scapula, already noticed, seems to show that the fore leg was adapted to co-operate with the tusks and teeth, in digging and separating large vegetables from the bottom. The great length attributed to the body, would have been no way inconvenient to an animal living in the water, but attended with much mechanical disadvantage to so weighty a quadruped upon land. In all these characters of a gigantic, herbivorous, aquatic quadruped, we recognise adaptations to the lacustrine condition of the earth, during that portion of the tertiary periods, to which the existence of these seemingly anomalous creatures appears to have been limited.
As it will be quite impossible, in the present Treatise, to give particular descriptions of the structure, even of a few of the fossil Mammalia, which have been, as it were, restored again to life by the genius and industry of Cuvier; I shall endeavour to illustrate, by the details of a single species, the method of analytical investigation, that has been applied by that great philosopher to the anatomy both of fossil and recent animals.