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In the survey which I have taken in the present course of lectures of the genesis, succession, geographical distribution, affinities, and osteology of the mammalian class, if I have succeeded in demonstrating the perfect adaptation of each varying form to the exigencies, and habits, and well-being of the species, I have fulfilled one object which I had in view, viz. to set forth the beneficence and intelligence of the Creative Power.

If I have been able to demonstrate a uniform plan pervading the osteological structure of so many diversified animated beings, I must have enforced, were that necessary, as strong a conviction of the unity of the Creative Cause.

If, in all the striking changes of form and proportion which have passed under review, we could discern only the results of minor modifications of the same few osseous elements,—surely we must be the more strikingly impressed with the wisdom and power of that Cause which could produce so much variety, and at the same time such perfect adaptations and endowments, out of means so simple.

For, in what have those mechanical instruments,—the hands of the ape, the hoofs of the horse, the fins of the whale, the trowels of the mole, the wings of the bat,—so variously formed to obey the behests of volition in denizens of different elements—in what, I say, have they differed from the artificial instruments which we ourselves plan with foresight and calculation for analogous uses, save in their greater complexity, in their perfection, and in the unity and simplicity of the elements which are modified to constitute these several locomotive organs 1

Everywhere in organic nature we see the means not only subservient to an end, but that end accomplished by the simplest means. Hence we are compelled to regard the Great Cause of all, not like certain philosophic ancients, as a uniform and quiescent mind, as an all pervading anima mundi, but as an active and anticipating intelligence.

By applying the laws of comparative anatomy to the relics of extinct races of animals contained in and characterizing the different strata of the earth's crust, and corresponding with as many epochs in the earth's history, we make an important step in advance of all preceding philosophies, and are able to demonstrate that the same pervading, active, and beneficent intelligence which manifests His power in our times, has also manifested His power in times long anterior to the records of our existence.

Eut we likewise, by these investigations, gain a still more important truth, viz. that the phenomena of the world do not succeed each other with the mechanical sameness attributed to them in the cycles of the Epicurean philosophy; for we are able to demonstrate that the different epochs of the earth were attended with corresponding changes of organic structure; and that, in all these instances of change, the organs, as far as we could comprehend their use, were exactly those best suited to the functions of the being. Hence we not only show intelligence evoking means adapted to the end; but, at successive times and periods, producing a change of mechanism adapted to a change in external conditions. Thus the highest generalizations in the science of organic bodies, like the Newtonian laws of universal matter, lead to the unequivocal conviction of a great First Cause, which is certainly not mechanical.

Unfettered by narrow restrictions,—unchecked by the timid and unworthy fears of mistrustful minds, clinging, in regard to mere physical questions, to beliefs, for which the Author of all truth has been pleased to substitute knowledge,—our science becomes connected with the loftiest of moral speculations.

If I believed,—to use the language of a gifted contemporary,— that the imagination, the feelings, the active intellectual powers, bearing on the business of life, and the highest capacities of our nature, were blunted and impaired by the study of physiological and palaeontological phenomena, I should then regard our science as little better than a moral sepulchre, in which, like the strong man, we were burying ourselves and those around us in ruins of our own creating.

But surely we must all believe too firmly in the immutable attributes of that Being, in whom all truth, of whatever kind, finds its proper resting-place, to think that the principles of physical and moral truth can ever be in lasting collision1.

1 Sedgwick, Address to the Geological Society, 1831.



With reference to the 'Transmutation of Species.'

For about two centuries, naturalists have been cognizant of a small ape, tailless, without cheek-pouches, and without the ischial callosities, clothed with black hair, with a facial angle of about 60°, and of a physiognomy milder and more human-like than in the ordinary race of monkeys, less capricious, less impulsive in its habits, more staid and docile. This species, brought from the West Coast of Africa, is that which our anatomist, Tyson, dissected: he described the main features of its organisation in his work published in 16991. He called it the Homo Sylvestris, or pigmy. It is noted by Linnaeus, in some editions of his Systema Naturae, as the Homo Troglodytes. Blumenbach, giving a truer value to the condition of the innermost digit of the hind foot, which was like a thumb, called it the Simia Troglodytes; it afterwards became more commonly known as the 'Chimpanzee.'

At a later period, naturalists became acquainted with a similar kind of ape, of quiet docile disposition, with the same sad, humanlike expression of features. It was brought from Borneo or Sumatra; where it is known by the name of Orang, which, in the language of the natives of Borneo, signifies 'man,' with the distinctive addition of Outan, meaning 'Wood-man,' or 'Wild Man of the Woods.' This creature differed from the pigmy, or Simia Troglodytes of Africa, by being covered with hair of a reddish-brown colour, and by having the anterior, or upper limbs, much longer in proportion, and the thumb upon the hind feet somewhat less. It was entered in the zoological catalogue as the Simia Satyrus. A governor of Batavia, Baron Wurmb, had transmitted to Holland, in 1780, the skeleton of a large kind of ape, tailless, like this small species from Borneo, but with a much-developed face, and large canine teeth, and bearing thick callosities upon the cheeks, giving it, upon the whole, a very baboon-like physiognomy; and he called it the Pongo.

At the time when Cuvier revised his summary of our knowledge of the animal kingdom, in the second edition of his 'Eigne Animal,'

1 ' Orang-Outang, she Homo sylvestris; or the Anatomie of a Pygmie, compared with that of a Monkey, an Ape and a Man,' 4to, 1699.

1829, the knowledge of the anthropoid apes was limited to these three forms. It had been suspected that the pongo might be the adult form of the orang; but Cuvier, pointing to its distinctive characters, suggested that it could hardly be the same species. The facial angle of the small red orang of Borneo, and of the small black chimpanzee of Africa, brought them, from the predominant cranium, and small size of the jaws and small teeth, nearer than any other known mammalian animal to the human species, particularly to the lower, or negro forms. It was evident, from the examination of these small chimpanzees and orangs, that they were the young of some large species of ape. The small size and number of their teeth, (there being, in some of the smaller specimens, only twenty, like the number of deciduous teeth in the human species,) and the intervals between those teeth, all showed them to be of the first or deciduous series. In 1835 I availed myself of the rich materials in regard to these animals collected about that time by the Zoological Society, to investigate the state of dentition, especially that of the permanent teeth which might be hidden in the substance of the jaws, of both the immature orangoutang and the chimpanzee, and I found that the germs of those teeth in the orang-outang agreed in size with the permanent teeth that were developed in the jaws of a species of the pongo of Wurmb, which Sir Stamford Raffles had presented to the museum of the College of Surgeons some years before. Specimens of orangs since acquired, of an intermediate age, have shown the progressive change of the dentition.

In the substance of the jaw were found the germs of the great canines, and of large bicuspid teeth; foreshowing the changes that must take place when the jaw is sufficiently enlarged to receive permanent teeth of this kind; and, when the rest of the cranium is modified, concomitantly, for the attachment of muscles to work the jaw so armed, denoting that all these changes must result in the acquisition of characters such as are presented by the skulls of the large pongo, or Bornean baboon-like ape. The specific identity of the pongo with certain of the young orang-outangs, was thus satisfactorily made out, and is now admitted by all naturalists. With regard to the chimpanzee, the germs of similarly proportioned large teeth were also discovered in the jaws, indicating, in like manner, that it must be the young of a much larger species of ape.

The principal osteological characters of the chimpanzee and orang, commencing from the vertebral column, are as follows:— The vertebral column describes only one curve, inclining forward, where it supports the head with its large jaws and teeth. The vertebrae in the neck, seven in number as usual in the mammalia, are chiefly remarkable for the great length of the simple spinous processes developed more than in most of the inferior apes, in relation to the necessities of the muscular masses that are to sustain and balance the head that preponderates so much forward on the neck. The vertebrae maintain a much closer correspondence in size, from the cervical to the dorsal and lumbar region, than in the human skeleton. With regard to the dorsal vertebrae, or those to which moveable ribs are articulated, there are twelve pairs in the orang; seven of them send cartilages to join the sternum, which is more like the sternum in man than in any of the inferior quadrumana: it is shorter and broader. In the smaller long-armed apes (Hylobates), which make the first step in the transition from the ordinary quadrumana to the man-like apes, the sternum is remarkably broad and short. The lumbar vertebrae are, originally, five in number in the orang; but one or two may coalesce with the sacrum. The sacrum is broader than in the lower quadrumana, but it is still narrow in comparison with its proportions in man. The pelvis is longer. The iliac bones are more expanded than in the lower quadrumana, but on the same plane, and are flattened and long. The tuberosities of the ischia are remarkably developed, and project outward. All these conditions of the vertebral column indicate an animal capable only of a semi-erect position, and present a modification of the trunk much better adapted for a creature destined for a life in trees, than one that is to walk habitually erect upon the surface of the ground. But that adaptation of the skeleton is still more strikingly shown in the unusual development of the upper prehensile extremities. The scapula is broad, with a well-developed spine and acromion; there is a complete clavicle; the bone of the arm (humerus) is of remarkable length, in proportion to the trunk; the radius and the ulna are also very long, and unusually diverging, to give increased surface of attachment to muscles; the hand is remarkable for the length of the metacarpus, and of the phalanges, which are slightly bent towards the palm; the thumb is less developed than the corresponding digit in the foot; the whole hand is admirably adapted for retaining a firm grasp of the boughs of trees. In the structure of the carpus, there is a well-marked difference from the human

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