successive conquerors of Syria for ages,—a low race of people, and described by trustworthy travellers as being as black as any of the Ethiopian races. Others of the Jewish people, participating in European civilization, and dwelling in the northern nations, shew instances of the light complexion, the blue eyes, and light hair of the Scandinavian families. The condition of the Hebrews, since their dispersion, has not been such as to admit of much admixture by the proselytism of household slaves. We are thus led to account for the differences in colour, by the influence of climate, without having to refer them to original or specific distinctions.

As to the difference in size in mankind, it is slight in comparison with what we observe in the races of the domestic dog, where the extremes of size are much greater than can be found in any races of the human species.

With reference to the modifications of the bony structure, as characteristic of the races of mankind, they are almost confined to the pelvis and the cranium. In the pelvis the difference is a slight, yet apparently a constant one. The pelvis of the adult negro may sometimes be distinguished from that of the European by the greater proportional length and less proportional breadth of the iliac bones; but how trifling is this difference compared with that marked distinction in the pelvis which the gorilla and orangoutang present!

With regard to the cranial differences, I have selected for comparison three extreme specimens of skulls characteristic of race: one of an aboriginal of Van Diemen's Land (the lowest of the Melanian or dark-coloured family), a well-marked Mongolian, and a wellformed European skull. The differences are chiefly these. In the low, uneducated, uncivilised races, the brain is rather smaller than in the higher, more civilised, and more educated races; consequently the cranium rises and expands in a less degree. Concomitant with this contraction of the brain-case is a greater projection of the fore part of the face; whether it may be from a longer exercise of the practice of suckling, or a more habitual application of the teeth in the premaxillary part of the jaw, and in the corresponding part of the lower jaw, in biting and gnawing tough, raw, uncooked substances, the anterior alveolar part of the jaws does project more in those lower races; but still to an insignificant degree compared with the prominence of that part of the skull in the large apes. And while alluding to them, I may again advert to the distinction between them and the lowest of the

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human races, which is afforded by the pre-maxillary bone, already referred to. In the young orang-utan, even when the change of dentition has begun, the suture between that bone and the maxillary is present; and it is not until the large canine teeth are developed, that the stimulus of the vascular system, in the concomitant expansion and growth of the alveoli, tends to obliterate the suture. In the young chimpanzee, the maxillary suture disappears earlier, at least on the facial surface of the upper jaw. In the human subject those traces disappear still earlier, and in regard to the exterior alveolar plates, the inter-maxillary and maxillary bones are connate. But there may be always traced in the human fœtus the indications of the palatal and nasal portions of the maxillo-intermaxillary suture, of which the poet Goethe was the first to appreciate the full significance.

In the Mongolian skull there is a peculiar development of the cheek-bones, giving great breadth and flatness to the face, a broad cranium, with a low forehead, and often with the sides sloping away from the median sagittal tract, something like a roof; whereas, in the European, there is combined, with greater capacity of the cranium, a more regular and beautiful oval form, a loftier and more expanded brow, a minor prominence of the malars, and a less projection of the upper and lower jaws. All these characteristics necessarily occasion slight differences in the facial angle. On a comparison of the basis cranii, the strictly bimanous characteristics in the position of the foramen magnum and occipital condyles, and of the zygomatic arches, are as well displayed in the lowest as in the highest varieties of the human species.

With regard to the value to be assigned to the above defined distinctions of race:-in consequence of not any of these differences being equivalent to those characteristics of the skeleton, or other parts of the frame, upon which specific differences are founded by naturalists in reference to the rest of the animal creation, I have come to the conclusion that Man forms one species, and that these differences are but indicative of varieties. As to the number of these varieties :—from the very well marked and natural character of the species, just as in the case of the similarly natural and circumscribed class of birds, scarcely any two ethnologists agree as to the number of the divisions, or as to the characters upon which those varieties are to be defined and circumscribed. In the subdivision of the class of birds, the ornithological systems vary from two orders to thirty orders; so with man there are classifications of

races varying from thirty to the three predominant ones which Blumenbach first clearly pointed out, the Ethiopian, the Mongolian, and the Caucasian or Indo-European. These varieties merge into one another by easy gradations. The Malay and the Polynesian link the Mongolian and the Indian varieties; and the Indian is linked by the Esquimaux again to the Mongolian. The inhabitants of the Andaman Islands, New Caledonia, New Guinea, and Australia, in a minor degree seem to fill up the hiatus between the Malayan and the Ethiopian varieties; and in no case can a well marked definite line be drawn between the physical characteristics of allied varieties, these merging more or less gradationally the one into the other.

In considering the import and value of the osteological differences between the gorilla-the most anthropoid of all known brutes —and man, in reference to the hypothesis of the origination of species of animals by gradual transmutation of specific characters, and that in the ascending direction:-it may be admitted that the skeleton is modifiable to a certain extent by the action of the muscles to which it is subservient, and that in domesticated races the size of the animal may be brought to deviate in both directions from the specific standard. By the development of the processes, ridges, and crests, and also by the general proportions of the bones themselves, especially those of the limbs, the human anatomist judges of the muscular power of the individual to whom a skeleton under comparison has appertained.

The influence of muscular actions in the growth of bone is more strikingly displayed in the change of form which the cranium of the young carnivore or the sternum of the young bird undergoes in the progress of maturity; not more so, however, than is manifested in the progress of the development of the cranium of the gorilla itself, which results in a change of character so great, as almost to be called a metamorphosis.

In some of the races of the domestic dog, the tendency to the development of parietal and occipital crista is lost, and the cranial dome continues smooth and round from one generation of the smaller spaniel, or dwarf pug, e.g. to another; while, in the large deerhound, those bony crista are as strongly developed as in the wolf, Such modifications, however, are unaccompanied by any change in the connexions, that is, in the disposition of the sutures, of the cranial bones; they are due chiefly to arrests of development, to retention of more or less of the characters of immaturity: even

the large proportional size of the brain in the smaller varieties of house-dog is in a great degree due to the rapid acquisition by the cerebral organ of its specific size, agreeably with the general law of its development, but which is attended in the varieties cited by an arrest of the general growth of the body, as well as of the particular developments of the skull in relation to the muscles of the jaws.

No species of animal has been subject to such decisive experiments, continued through so many generations, as to the influence of different degrees of exercise of the muscular system, difference in regard to food, association with man, and the concomitant stimulus to the development of intelligence, as the dog; and no domestic animal manifests so great a range of variety in regard to general size, to the colour and character of the hair, and to the form of the head, as it is affected by different proportions of the cranium and face, and by the intermuscular crests superadded to the cranial parietes. Yet, under the extremest mask of variety so superinduced, the naturalist detects in the dental formula and in the construction of the cranium the unmistakeable generic and specific characters of the Canis familiaris.

This and every other analogy applicable to the present question justifies the conclusion that the range of variety allotted to the gorilla, chimpanzee, and orang-utan, under the operation of external circumstances favourable to their higher development, would be restricted to differences of size, of colour, and other characters of the hair, and of the shape of the head, in so far as this is influenced by the arrest of general growth after the acquisition by the brain of its mature proportions, and by the development, or otherwise, of processes, crests, and ridges for the attachment of muscles. The most striking deviations from the form of the human cranium which that part presents in the great orangs and chimpanzees result from the latter acknowledged modifiable characters, and might be similarly produced; but not every deviation from the cranial structure of man, nor any of the important ones upon which the naturalist relies for the determination of the genera Troglodytes and Pithecus, have such an origin or dependent relation. The gorilla, indeed, differs specifically from both the orang and man in one cranial character, which no difference of diet, habit, or muscular exertion can be conceived to affect.

The prominent superorbital ridge, for example, is not the consequence or concomitant of muscular development; there are no muscles attached to it that could have excited its growth. It is a

characteristic of the cranium of the genus Troglodytes from the time of birth to extreme old age; by the prominent superorbital ridge, for example, the skull of the young gorilla or chimpanzee with deciduous teeth may be distinguished at a glance from the skull of an orang at the same immature age; the genus Pithecus, Geoffr., being as well recognised by the absence, as the genus Troglodytes is by the presence, of this character. We have no grounds, from observation or experiment, to believe the absence or the presence of a prominent superorbital ridge to be a modifiable character, or one to be gained or lost through the operations of external causes, inducing particular habits through successive generations of a species. It may be concluded, therefore, that such feeble indication of the superorbital ridge, aided by the expansion of the frontal sinuses, as exists in man,. is as much a specific peculiarity of the human skull, in the present comparison, as the exaggeration of this ridge is characteristic of the chimpanzees and its suppression of the orangs.

The equable length of the human teeth, the concomitant absence of any diastema or break in the series, and of any sexual difference in the development of particular teeth, are to be viewed by the light of actual knowledge, as being primitive and unalterable specific peculiarities of man.

Teeth, at least such as consist of the ordinary dentine of mammals, are not organised so as to be influenced in their growth by the action of neighbouring muscles; pressure upon their bony sockets may affect the direction of their growth after they are protruded, but not the specific proportions and forms of the crowns of teeth of limited and determinate growth. The crown of the great canine tooth of the male Troglodytes gorilla began to be calcified when its diet was precisely the same as in the female, when both sexes derived their sustenance from the mother's milk. Its growth proceeded and was almost completed before the sexual development had advanced so as to establish those differences of habits, of force, of muscular exercise, which afterwards characterise the two sexes. The whole crown of the great canine is, in fact, calcified before it cuts the gum or displaces its small deciduous predecessor; the weapon is prepared prior to the development of the forces by which it is to be wielded; it is therefore a structure fore-ordained, a predetermined character of the great ape, by which that creature is made physically superior to man; and one can as little conceive the development of the canine tooth to be a result of external