Page:Evolution of Life (Henry Cadwalader Chapman, 1873).djvu/21



cannot glance at the opening pages of any work on Zoology without being struck with the difficulty that naturalists experience in classifying the objects of their study. This difficulty arises from the fact of there being many animals whose organization presents characters which combine the peculiarities of different families or orders. The Flying Lemur (Galeopithecus volans) of the East Indies was for a long time considered to be a bat; modern anatomists place it among the monkeys, and yet, according to some authorities, the grounds for its determination in the one case are as good as in the other. If the Galeopithecus, the monkeys and the bats originally appeared as we find them now, why should there be such a difficulty in determining their place in the Animal Kingdom? If, however, there has been an order of Galeopitheci, of which the present species are the only surviving representatives, and we regard these extinct forms as the common ancestors of the bats and the monkeys, we have an explanation of the peculiarities which are shared by these three orders:

If the theory of the gradual transformation of animals be true, it is quite natural that we should find transitional (19)