PECULIAR ENDOWMENTS OP HUMAN HAND. 483 



ments of the thumb and fingers are concerned in its particular 

 applications. 



643. The hand of Man is distinguished from the extremity 

 of most Quadrupeds by its possession of an opposable thumb, 

 that is, of a finger which can be made to act in a direction 

 opposite to that of the rest. But among the Apes and 

 Monkeys, we find this peculiarity not only in the superior 

 extremity, but also in the inferior ; whence these animals are 

 said to be quadrumanous or four-handed, whilst Man is 

 bimanous, possessing two hands only. It must not be sup- 

 posed, however, that Apes and Monkeys are superior in this 

 respect to Man ; for they possess this distinguishing character 

 in a much less striking degree than he does. All the four 

 extremities of Apes and Monkeys possess the power of grasp- 

 ing, but they are all used also for support ; and we find that 

 in consequence of the shortness of the thumb and great toe, the 

 grasping power is very inferior to that which Man possesses. 

 But of the four extremities of Man, one pair is specially adapted 

 for support, and the other for prehension or grasping ; and this 

 by the length and mobility of the thumb, which is capable of 

 being brought into exact opposition to the extremities of 

 all the fingers, whether singly or in combination. But even 

 in those Quadrumana which most nearly approach Man, 

 the thumb is so short and weak, and the fingers so long 

 and slender, that their tips can scarcely be opposed to each 

 other, and then with only a slight degree of force ; hence, 

 although completely adapted for clinging round bodies of 

 a certain size, such as the small branches of trees, &c. the 

 extremities of the Quadrumana can neither seize very minute 

 objects with that precision, nor support large ones with that 

 firmness, which is essential to the dexterous performance of a 

 variety of actions for which the hand of Man is admirably 

 suited. Hence they may be more appropriately termed 

 claspers than hands. 



644. In many of the inferior Mammalia, whose extremities 

 are adapted for support only, we find each row of phalanges 

 consolidated into two bones, or even into one. This is the 

 case, for example, in the Ruminant Quadrupeds, as the Camel 

 (fig. 229), and in the Horse ( 652). Such an arrangement 

 obviously increases the firmness of the limb, though it 

 altogether deprives it of prehensile power. In other in- 



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