THE HUMAN SPECIES 



development of the muscular system peculiar to the latter. In 

 the face of the gorilla we miss the play of expression peculiar 

 to the human countenance, and it consequently appears dull 

 and lifeless. 



The thick muscular neck is clumsy and has but few joints. 

 The pectoralis major is enormously developed as are also the 

 muscles of the whole arm. In man, the upper arm, as well as 

 the fore-arm, tapers finely towards the hand and the muscles 

 of the fore-arm terminate in slender tendons, whereas in the 



M. abduct, poll, brev 

 M. flex. poll, brev 



M. lumbricales 



M. abduct, dig. V 

 M . opponens dig. V 



M. flex. dig. subl. 



Hiatus tendon, m. 

 flex. subl. 



M. flex. dig. pro- 

 fund. 



FIG. 44. Muscles of the human thumb and fifth ringer. 

 (Heitzmann-Zuckerkandl.) 



gorilla the two parts of the arm are almost equal in size through- 

 out their whole length. 



The nates, so well -developed in man, and the rounded finely 

 tapering femur, present a strong contrast to the corresponding 

 parts in the gorilla, where the nates are meagre and the adjoin- 

 ing thigh bones are pressed inwards. 



In man the lower part of the leg becomes smaller from the 

 rounded calf towards the ankle, whereas in the gorilla the con- 

 ditions are exactly reversed, the leg being even somewhat 



