39 



organization of the Orang, and that in which it differs most from 

 the Chimpanzee, consists in the relative lengtli of the upper and 

 lower extremities, the arras in the former reaching to the heel. The 

 articular surface of the head of the humerus forms a complete hemi- 

 sphere ; and in some specimens that bone is perforated between the 

 condyles. The principal peculiarities in the fore-arm consist in the 

 large space between the radius and ulna, occasioned by the outward 

 curve of the former, and in the absence of tlie acute margin on its 

 idnar aspect. The proportion borne by the radius to the ulna is in 

 Man as 11 to 12; in the Orang as SQ to 37. The bones of the 

 hand offer the same elongated form, with the exception of those of 

 the thumb, which does not reach to the end of the metacarpal bone 

 of the fore-finger. Those of the carpus have their ossification com- 

 pleted at a later period than in Man, and allow a freer motion upon 

 each other: the os pisiforme is divided into two. Of the fingers, 

 the proximal phalanges are more curved than in Man, and the dis- 

 tal more pointed, not expanding to afford support for an extended 

 surface of delicate touch. 



As the upper extremity of the Orang' exceeds in length that of the 

 Chimpanzee, so the lower differs as much in the contrary respect; 

 preserving throughout life much less than the foetal proportions of 

 the human subject. The femur has a straight shaft, no depression 

 on the head, a shorter neck forming a more obtuse angle with the 

 shaft, and no linea aspera posteriorly. The inner condyle not being 

 produced beyond the outer, the axis of the femur is in the same line 

 with that of the tibia, as in the Chimpanzee, The inward curve of 

 the tibia occasions a much larger space between it and the ^fibula 

 than in Man or in the Chimpanzee. The patella is smaller in pro- 

 ■ portion than in Man, of an oval shape, and with a single articulating 

 surface. The bones of the tarsus are numerically the same with 

 those of the Chimpanzee, and have the same general form, but ad- 

 mit of freer motion on each other. A greater degree of obliquity 

 in the articulating surface of the astragalus causes the whole foot to 

 be turned more inwards ; and the os calcis has still less projection back- 

 wards than the Chimpanzee. The internal cuneiform bone recedes 

 most from the human type in having a greater development towards 

 the tibial aspect, and in having the surface of articulation for the 

 hallux below the range of the other metatarsal bones, all of which 

 are much longer and more bent and have greater interspaces than 

 the human. That of the hallux extends very little beyond the mid- 

 dle of that of the second toe, and stands off from it at an acute angle. 

 The peculiarity of the structure of the hallux first noticed by Camper, 

 in seven out of eight Orangs observed by him, viz. its possessing 

 no ungueal phalanx and consequently no nail, loses much of its im- 

 portance as a specific character from the fact that the individual 

 dissected at the Society's Museum a few years since had very per- 

 fect, but small, black nails, and two phalanges, and that the same 

 number of phalanges exist in the natural skeleton of Lord Amherst's 

 Orang in the Museum of the College of Surgeons. The j)halangcs 

 of the other toes are remarkably elongated, and those of the first 



