THE EXTERNAL FORM OF ANTHROPOID APES. 40 



almost tearful expression- The neck is short, the 



trunk drawn out. On the long, narrow hand there 



is a short thumb, laterally compressed, which does 



not quite reach to the metacarpo-phalangeal joint. 



Tlie l)all of the last phalanx 



forms a thick, rounded 



pad, which is repeated in 



a lesser degree on the 



under side of the first 



phalanx of the thumb, 



and on its ball. The 



thumb-nail is bent back, 



as unlike a claw as the 



flattened, long, and narrow 



nails of the other fingers. 



The middle finger is only 



a little longer than the 



first, and the fourth not 



much shorter than the 

 third finger (Fig. 12). 



The foot is neatly made, 

 short and narrow, with- 

 out a projecting heel. 

 The great toe is very long, 

 reaching almost to the last 

 phalanx of the second toe. 

 The sole of the foot, and the under side of the great 

 toe, especially its last joint, are provided with thick, 

 rounded pads. The middle toe is not much longer 

 than the second, the fourth is shorter again, and the 

 fifth is only half as long as the fourth. There is 

 only a very short web between the roots of the 



Fig. 12. — Left hand of Hylobates 

 albimanus. 



