18 Professor Owen, [Feb. 4, 



which is the cerebrum largest, as compared with the cerebellum ? If 

 he found all these characters highest in the gorilla, he would not be 

 diverted from the just inference because the great size and surpassing 

 physical power attained in that species masked the true data from 

 obvious view. 



The comparative anatomist would look to the caecum and the ischial 

 integument: if he found in one subject of his comparisons ( Troglodytes') 

 a long " appendix vermiformis caeci," as in man, but no " callosities," 

 and in another subject {Hylobates') the ischial callosities but only a 

 short rudiment of the caecal appendix, he would know which of the two 

 tailless apes were to be placed next " the monkeys with ischial callosities 

 and no vermiform appendix," and which formed the closer link toward 

 man. He would find that the anthropoid intestinal and dermal charac- 

 ters were associated with the absolutely larger and better developed 

 brain in the gorilla, chimpanzee, and orang ; whilst the lower quad- 

 rumanous characters exhibited by the caecum and nates were exhibited 

 by the smaller- brained and longer-armed tailless gibbons. 



Pursuing the comparison through the complexities of the bony 

 framework, the comparative anatomist would first glance at the more 

 obvious characters ; and such, indeed, as would be given by the entire 

 animal. The characteristics of the limbs in man are their near equality 

 of length, but the lower limbs are the longest. The arms in man 

 reach to below the middle of the thigh ; in the gorilla they nearly attain 

 the knee ; in the chimpanzee they reach below the knee ; in the orang 

 they reach the ankle ; in the siamang they reach the sole ; in most gibbons 

 the whole palm can be applied to the ground without the trunk being 

 bent forward beyond its naturally inclined position on the legs. These 

 gradational differences coincide with other characters determining the 

 relative proximity of the apes compared with man. In no quadru- 

 mana does the humerus exceed the ulna so much in length as in man ; 

 only in the very highest and most anthropoid, viz. the gorilla and 

 chimpanzee, does it exceed the ulna at all in length ; in all the rest, as 

 in the lower quadrupeds, the fore-arm is longer than the arm. 



The humerus, in the gorilla, though less long, compared with the 

 ulna, than in man, is longer than in the chimpanzee ; in the orang it is 

 shorter than the ulna ; in the siamang and other gibbons it is much 

 shorter, the peculiar length of arm in those " long-armed apes" is 

 chiefly due to the excessive length of the antibrachial bones. 



The difference in the length of the upper limbs, as compared with 

 the trunk, is but little between man and the gorilla. The elbow-joint 

 in the gorilla, as the arm hangs down, is opposite the " labrum ilii," 

 the wrist opposite the " tuber ischii ;" it is rather lower down in the 

 chimpanzee ; is opposite the knee-joint in the orang ; and opposite the 

 ankle-joint in the siamang. 



Man's perfect hand is one of his peculiar physical characters ; that 

 perfection is mainly due to the extreme differentiation of the first from 

 the other four digits, and its concomitant power of opposing them 

 as a perfect thumb. An opposable thumb is present in the hand of 

 most quadrumana, but is usually a small appendage compared with 



