Prof. Owen on the. Gorilla. 381 



greater through the arrest of development of the lower limbs. Very 

 significant of the closer anthropoid affinities of the Gorilla is the 

 superior length of the arm (humerus) to the fore-arm, as compared 

 with the proportions of those parts in the Chimpanzee. The hair of 

 the arm inclines downward, that of the fore-arm upward, as in the 

 Chimpanzee. The thumb extends a little beyond the base of the 

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

 the metacarpal bone of that finger in the Chimpanzee or any other 

 ape : the thumb of the Siamang (Ilylobates syndactyla) is still 

 shorter in proportion to the length of the fingers of the same hand : 

 the philosophical zoologist will see great significance in this fact. In 

 man the thumb extends to, or beyond, the middle of the first pha- 

 lanx of the fore-finger. 



The fore-arm in the Gorilla passes into the hand with very slight 

 evidence, by constriction of the wrist, the circumference of which, 

 without the hair, was fourteen inches, that of a strong man averaging 

 eight inches. The hand is remarkable for its breadth and thickness, 

 and for the great length of the palm, occasioned both by the length 

 of the metacarpus and the greater extent of undivided integument 

 between the digits than in man ; these only begin to be free opposite 

 the middle of the proximal or first phalanges in the Gorilla. The 

 digits are thus short, and appear as if swollen and gouty ; and are 

 conical in shape after the first joint, by tapering to nails, which, being 

 not larger or longer than those of man, are relatively to the fingers 

 much smaller. The circumference of the middle digit at the first 

 joint in the Gorilla is 5^ inches ; in man, at the same part, it averages 

 2| inches. The skin covering the middle phalanx is thick and cal- 

 lous on the back of the fingers, and there is little outward appear- 

 ance of the second joint. The habit of the animal to apply those 

 parts to the ground, in occasional progression, is manifested by these 

 callosities. The back of the hand is hairy as far as the divisions of 

 the fingers ; the palm is naked and callous. The thumb, besides its 

 shortness, according to the standard of the human hand, is scarcely 

 half so thick as the fore-finger. The nail of the thumb did not ex- 

 tend to the end of that digit ; in the fingers the nail projected a little 

 beyond the end, but with a slightly convex worn margin, resembling 

 the human nails in shape, but relatively less. 



In the hind limbs, chiefly noticeable was that first appearance in 

 the quadrumanous series of a muscular development of the gluteus, 

 causing a small buttock to project over each tuber ischii. This 

 structure, with the peculiar expanse, as compared with other Qua- 

 drumana, of the iliac bones, leads to an inference that the Gorilla 

 must naturally and with more ease resort occasionally to station and 

 progression on the lower limbs than any other ape. 



The same cause as in the arm, viz. a cotitinuance of a large pro- 

 portion of fleshy fibres to the lower end of the muscles, coextensive 

 with the thigh, gives a great circumference to that segment of the 

 limb above the knee-joint, and a more uniform size to it than in man. 

 The relative shortness of the thigh, its bone being only eight-ninths 

 the length of the humerus (in man the humerus averages five-sixths 



