THE MONKEYS AND APES. I25, 



The two halves of the lower jaw are always co-ossified together, 

 when the animal is full grown. The humerus^ or arm bone, 

 never has an entepicondylar foramen on the inner side of its 

 lower portion, and the bones of the fore-arm (the ulna and 

 radius) are never ossified together, nor are those of the lower 

 leg (the tibia and fibula) ; 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 ^ts 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 Lemuroidea. The uterus is a simple and 

 not a two-horned sac, and its inner layer, in which the foetal 

 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 Ly nearly similar movements 

 of the muscles 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 



