THE MONKEYS AND APES. 125 
The two halves of the lower jaw are always co-ossified together, 
when the animal is full grown. The Aumerius, or arm-bone, 
never has an entepicondylar foramen on the inner side of its 
lower portion, and the bones of the fore-arm (the w/a and 
radius) are never ossified together, nor are those of the lower 
leg (the “7a and fidu/a) ; so that there is perfect freedom for 
every movement necessary for grasping and walking, or for 
rotating the hand or foot on the wrist and ankle. 
With regard to the brain, the anthropoid cerebrum, or fore- 
brain, is greatly convoluted, and differs from that of the 
Lemurs by its proportionately larger size, the cerebellum, or 
hind-brain, being as a rule entirely covered by it. 
The uterus and structures for the nutrition of the young 
prior to birth differ greatly in this Sub-order from the condi- 
tions existing in the Zemuromdea. The uterus is a simple and 
not a two-horned sac, and its inner layer, in which the fcetal 
and maternal structures intermingle during the growth of the 
embryo, is shed after the birth of the young, which is not the 
case in the Lemurs. 
“The resemblance of Monkeys to Man,” says Mr. Darwin, 
“is greatly caused by the relative position of the features of 
the face. The eyes are arched over; they are separated by a 
long nose, the end of which in some is very human. The 
mouth is not carried back, but occupies the same general 
position as in Man, and the forehead, so often wrinkled, is 
usually prominent and like that of a child. The likeness is in- 
creased by the fact that anger, sorrow, pleasure, and satisfac- 
tion, are displayed by the Monkey by nearly similar movements 
of the mscles and skin, chiefly above the eyebrows and round 
the mouth. Some few expressions are indeed almost the same, 
as in the weeping of certain kinds of Monkeys, and in the 
