Glass 6. Mammalia. Order 14. Primates. 535 



(c) The Chimpanzee* {Simia troglodytes or Troglodytes niger) and the 

 Gorilla* {8. ov T. gorilla) correspond in most points. The forehead slopes 

 back, the nose is broad and flat, but projects further than in the Orang; the 

 fore limbs also are shorter, the hands and feet broader, the hallux large and 

 well-developed ; both ai-e black. The Gorilla attains a height of 1"7 m. ; the 

 Chimpanzee is somewhat smaller. Both occur in the tropical parts of West 

 Africa. 



Sub-Order 3. AnthropidSB. (Man.) 



In contrast to other Primates, the Anthropidse are characterised 

 by the specialisation of the hind limbs as organs of loco- 

 motion adapted for supporting the body in an upright position 

 without assistance from the fore limbs. In correlation with this 

 they are very powerful, much longer than the fore Hmbs^ and 

 extremely muscular. The hallux is but little more separated 

 from the other toes than these from one another,t possesses only 

 a slight power of independent movement and is not opposable ; it is 

 somewhat longer than, or about -equal in length to, the second digit, 

 or a very little shorter (in other Primates much shorter) ; the other 

 four toes are short, the metatarsus long. The pelvis is very short and 

 broad, the ilia in particular are very shorty broad, and strongly curved ; 

 the symphysis is short. The fore limbs, which are very like those of 

 the Anthropoid Apes, are relatively weaker than in the latter ; they 

 are extremely well developed as prehensile organs, but are of no 

 importance for the ordinary mode of locomotion. Another character- 

 istic point is the enormous development of the brain,f and the 

 consequent abnormal preponderance of the cranial capsule over the 

 slightly developed facial region : in other respects the structure of 

 the brain, even as regards points of detail, is very like that of the 

 Anthropoid Apes. Further peculiarities are the slight covering of 

 hair over the greater portion of the body; the small size of the canine 

 tooth ; and a feature which is closely connected with this, the absence 

 of a diastema between the external incisor and the canine of the upper 

 jaw larger than between the other teeth (in other Primates the canine 

 of the lower jaw bites into this space) ; lastly it must be mentioned 

 that the thoracic cavity is still broader and flatter than in the 

 Anthropoid Apes. 



* Possibly several closely allied species are included under each of these titles. 



t The gap, however, is clearly deeper, and the distance between the hallux and the 

 second toe is greater than between the other toes ; still greater and more distinct in 

 the embryo and young ehUd than in the adult. 



X Man, however, does not possess the largest brain as compared with the whole 

 weight of the body ; even among the Primates, a relatively larger brain occurs in some 

 small forms (in one of the Hapahdae, the weight of the brain, when compared with that 

 of the whole body, is as 1 : 20, in Man it averages 1 : 40). On the other hand, the 

 brain of Man is much larger than in any other animal of similar size (the brain of the 

 Oorilla, relatively to the weight of the body, is 1 : 200). 



