158 



THE GENERAL ANATOMY OF GORILLA 



[sect, a 



styled sub-species. (The problem is identical with that of the 

 taxonomic description of the several Races of Mankind.) A recent 

 writer (Rothschild, op. tit., v. p. 153 supra), adopts a trinomial 

 mode of classification, and recognizes a single genus and species 

 of Gorilla with five sub-species 1 . 



A. General External Characters-. The preceding illus- 

 tration (Fig. 99) will furnish a better idea of the general 

 appearance of an adult male Gorilla 

 than could be conveyed by many 

 lines of text. A noteworthy feature 

 is the span of the arms, which often 

 exceeds eight feet. The animal has 

 retained here at least one "arboreal " 

 character. On level ground, the 

 Gorilla moves in a crouching atti- 

 tude, using the arms somewhat like 

 crutches. The fingers are then bent 

 and the skin on the dorsal aspect 

 of the terminal joints becomes thick 

 and callous. (In the longer-armed 

 Orang-utan, the whole length of the 

 fingers as far as the knuckles, is applied to the ground.) The 

 thumbs are small and feeble ; the great toe on the contrary very 

 powerful, though shorter than the other toes (cf. Fig. 100), which are 

 usually " webbed." The latter phenomenon may also be regarded 



1 The names are as follows. 



1. Gorilla gorilla gina. 



2. ,, ,, manyema. 



3. ,, ,, matschiei. 



4. ,, ,, diehli. 



5. ,, ,, beringeri. 



Probably other sub-species may be discovered. There is no doubt that individuals 

 often exceed the average dimensions so much as to be veritable "giant-forms" of 

 Gorilla. 



Lord Rothschild recognizes five species of Chimpanzee, and one species of 

 Orang-utan with at least four sub-species. The Gibbons (Hylobates) fall into 

 a single genus with several species and probably several sub-species also. 



- In the Proceedings of the Zoological Society, 7th March 1899, will be found an 

 admirable comparison, by Keith, of the general systematic anatomy of Chimpanzee 

 and Gorilla. 



Fig. 100. Hand and foot of adult 

 male Gorilla. 



