EXTERNAL FORM OF THE MAN-LIKE APES. 751 



region resembles the projecting rump of a fowl, and this may also be 

 observed in the young gorilla and chimpanzee. The long, muscular 

 arms reach to the ankles when the animal is in an erect position, and 

 are altogether out of proportion with the rest of the body. The pow- 



FiG. 7.— Head and SHOtrLDEKS op an Aged Male Orang-Gutanq. 



erful upper arm is shorter than the lean forearm. The hand is long 

 and narrow. The thumb, which reaches as far as the metacarpo- 

 phalangeal joint, has a displeasing and almost rudimentary effect. A 

 web unites the fingers, sometimes extending along a third of the first 

 phalanx, sometimes along half. The middle 

 finger is somewhat longer than the first and 

 third fingers, and the third is next to it in 

 length. The fourth finger is comparatively 

 long. The palm of the hand is flat, only marked 

 by a few deep furrows. The long, slender 

 fingers are laterally compressed, and the nails 

 on their tapering ends are arched. 



The thighs, somewhat compressed on the 

 inner side, are, however, very muscular, but 

 become much smaller on their back side. The 

 calf of the leg is less developed than in the gorilla, or even than in 

 the chimpanzee. The feet are, like the hands, long and slender. The 

 narrow, flat heels, project very slightly behind. The great-toes are 

 short, with wide extremities, rounded above, and provided on the sole 

 with thick, fatty skin. In old age these animals not only often lose 

 the nails of their great-toes, but sometimes even the last phalanges 

 themselves. This is not merely a disease produced by confinement, 

 as is the case with sea-cat monkeys, hyenas, etc., wHich in this condi- 



PiG. 8.— Ear of the Orang- 

 outang. 



