THE MAN-LIKE APES 



those of the other toes. In this respect, as the figure shows, the foot of man is 

 markedly different from that of the gorilla and the other apes. With the curious 

 exception of the orang, in which the great toe is often entirely devoid of any trace 

 of such appendage, all the fingers are furnished with nails. In the higher forms 

 these nails are of a flattened shape in all the digits ; and this flatness is always 

 characteristic of the nail of the great toe, 

 although the other digits of the lower forms 

 have curved nails. In order to form an 

 efficient support for these nails, the bones of 

 the terminal joints of the digits, with the ex- 

 ception of the index finger of the lemurs, are 

 transversely flattened out ; and are thus very 

 different from those of the Rodents and Car- 

 nivores. That the hand and foot should 

 have perfect freedom of motion, it is of 

 course necessary that the bones of the fore- 

 arm and lower leg shoiild remain completely 

 separate from one another ; and, as we see 

 from the figured skeletons, the radius and 

 ulna in the fore-arm, and the tibia and fibula 

 in the leg, are both equally well developed 

 and capable of motion upon one another. 

 Another important point as regards the free 

 use of the arms is the presence of complete 

 collar-bones, which are always well developed 

 in apes and monkeys, as they are in ourselves. 



If we look once more at the figures of 

 the skeletons of man and the gorilla we shall 

 not fail to observe that in the skull the 

 sockets, or orbits, of the eyes are completely 

 surrounded by a ring of bone, and that the 

 sockets themselves look almost directly for- 

 wards. This complete bony ring round the 

 eye-sockets at once serves to distinguish the 

 skulls of all the Primates from those of most 

 of the Carnivores. 



In correlation with the herbivorous habits 

 of the majority of the species, the teeth of the 

 Primates are adapted for grinding ; the cheek- 

 teeth having broad flattened crowns, which may either, as in ourselves, be sur- 

 mounted by tubercles, or by transverse ridges. Except in one family of American 

 monkeys, there are always three molar teeth in each side of either jaw, the last 

 of which corresponds with our own "wisdom-tooth"; and these molar teeth are 

 invariably larger and more complicated than the premolars. Very generally, as 

 in ourselves, the number of the latter teeth is reduced to two on each side, and 



SKELETON OF THE GORILLA. 



