CHAR A CTERISTICS. 
i7 
parallel to 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 lingers 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 
exception of the index finger of the lemurs, 
are transversely flattened out; and are thus 
very different from those of the Rodents and 
Carnivores. 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 should 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 sur¬ 
rounded 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 surmounted 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 no living member of the order has more than 
vol. 1.—2 
SKELETON OF THE GORILLA ; 
and male (c?) and (<^) female skulls. 
