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pared with that of Man. It is relatively largest in the Gorilla. In 

 this ape the thumb reaches to a little beyond the base of the first 

 phalanx of the fore-finger ; it does not reach to the end of the meta- 

 carpal bone of the fore-finger in the Chimpanzee, Orang, or Gibbon ; 

 it is relatively smallest in the last tailless ape. In Man the thumb 

 extends to or beyond the middle of the first phalanx of the fore- 

 finger. The philosophical zoologist will see great significance in the 

 results of this comparison. Only in the Gorilla and Chimpanzee are 

 the carpal bones eight in number, as in man ; in the Orangs and 

 Gibbons they are nine in number, as in the tailed monkeys. 



The scapulae are broader in the Gorilla than in the Chimpanzee, 

 Orang, or long-armed apes ; they come nearer to the proportions of 

 that bone in Man. But a more decisive resemblance to the human 

 structure is presented by the iliac bones. In no other ape than the 

 Gorilla do they bend forward, so as to produce a pelvic concavity ; 

 nor are they so broad in proportion to their length in any ape as in 

 the Gorilla. In both the Chimpanzee and Orang the iliac bones are 

 flat, or present a concavity rather at the back than at the fore part. 

 In the Siamang they are not only flat, but are narrower and longer, 

 resembling the iliac bones of tailed monkeys and ordinary quadrupeds. 



The lower limbs, though characteristically short in the Gorilla, 

 are longer in proportion to the upper limbs, and also to the entire 

 trunk, than in the Chimpanzee ; they are much longer in both pro- 

 portions and more robust than in the Orangs or Gibbons. But the 

 guiding points of comparisons here are the heel and the hallux. 



The heel in the Gorilla makes a more decided backward projection 

 than in the Chimpanzee ; the heelbone is relatively thicker, deeper, 

 more expanded vertically at its hind end, beside being fully as long 

 as in the Chimpanzee : it is in the Gorilla shaped and proportioned 

 more like the human calcaneum than in any other ape. Among all 

 the tailless apes the calcaneum in the Siamang and other Gibbons 

 least resembles in its shape or proportional size that of Man. 



Although the foot be articulated to the leg with a slight inversion 

 of the sole it is more nearly plantigrade in the Gorilla than in the 

 Chimpanzee. The Orang departs far, and the Gibbons farther, from 

 the human type in the inverted position of the foot. 



The great toe which forms the fulcrum in standing or walking is, 

 perhaps, the most characteristic peculiarity in the human structure ; 

 it is that modification which differentiates the foot from the hand, 

 and gives the character to the order Bimana. In the degree of its 

 approach to this development of the hallux the quadrumanous animal 

 makes a true step in affinity to Man. 



The Orang-utan and the Siamang, tried by this test, descend far 

 and abruptly below the Chimpanzee and Gorilla in the scale. In the 

 Orang the hallux does not reach to the end of the metacarpal of the 

 second toe ; in the Chimpanzee and Gorilla it reaches to the end of 

 the first phalanx of the second toe ; but in the Gorilla the hallux is 

 thicker and stronger than in the Chimpanzee. In both, however, 

 it is a true thumb, by position, diverging from the other toes, in the 

 Gorilla, at an angle of 60° from the axis of the foot. 



