Page:Natural History Review (1862).djvu/15

4 uses ae those for which we employ hands; the Carajas who contriye to steal and hide away even fish-hooks, with their feet, from their unsuspecting visitors; and he might have added, the treacherous Australian savages, who commonly pretend to approach unarmed, but all the while drag their spears through the grass with their toes.

Leaving aside the famous Miss Biffin, and the painter Ducornet, who may, or might, be seen in Paris, executing historical pictures on the great scale with his feet, there is ample evidence, that, of the elements of the definition of a hand given by M. St. Hilaire, only the elongation and deep division of the digits can be retained, even for Man. In Man in fact, while the longest interdigital cleft of the hand is rather less than half as long as the whole hand, the longest interdigital cleft of the foot is, as we have said, but little more than a fifth as long as the whole foot. Here, therefore, the distinction is clear. But in the Marmoset (Hapale) the longest interdigital cleft between the toes of the terminal division of the hind member is not more than 2-7ths as long as the whole division. So that if the whole length of the terminal division of a limb be taken as 35, the length of the longest interdigital space of the human hand may be taken as about 16, that of the human foot as about 7, and that of the hind limb of Hapale as 10. So that, judged even by this test, the latter is much more of a foot than a hand.

M. St. Hilaire's definition then seems as complete a failure as all the other attempts which have been made to justify the application of the title "four-handed" to the apes—a failure which becomes still more conspicuous, if, leaving the external features of the hand and foot, we turn to their anatomical structure; by which it may be readily demonstrated, that the arrangement of the bones and muscles of the terminal segment of the hind limb of every ape whatsoever is, in all essential respects, similar to that which obtains in the foot of man and other mammals, and is totally different from that found in the hand of man and in the terminal segment of the fore limb of other mammals. In fact, there is no four-handed mammal in existence: no mammal, that is, the terminal segments of whose hind limbs are not far more like the foot of man than they are like his hand. The terminal segments of the fore and hind limos of mammals have their several and distinct plans of construction, and in no case does a hind terminal segment take on the plan of a fore segment or the reverse. Either may become prehensile, but a prehensile foot, such as the apes and opossums possess, is a totally different thing from a hand.