178 MR. ST. a. mVAET ON THE SKELETON OF THE PRIMATES. 



as in Man and the Gorilla, the most extended one, nor is it equal to the axillary one, 

 as sometimes in the Chimpanzee ; but it is absolutely shorter. The part of it which 

 is superior to the origin of the spine is much shorter, as compared wth the part 

 below", than is the case in Man, and very much more so than in Troglodytes, from 

 three-fourths to five-sixths of the vertebral margin being below the origin of the spine. 

 If not straight, this margin is very slightly convex, and scarcely ever* presents a trace 

 of sigmoid curvature, the part at or near to the origin of the spine being sometimes" 

 more prominent than the rest, instead of less so as in Troglodytes. 



The axillary margin is unlike that of the higher forms in that it is decidedly 

 convex (PL XXXV. fig. 1) in almost all cases, though in the variety Morio it is 

 more nearly straight (PL XXXV. fig. 3). The ridge near the glenoid surface, for the 

 attachment of the triceps, is jjrominent, and, as in Troglodytes, is continued a longer 

 distance, and bounds externally a much wider groove than is the case in Man. 



The superior ^'ertebral angle, though very distinctly marked, is much less produced 

 than in Man and Troglodytes; hence the very slight concavity of the upper margin 

 (PL XXXV. fig. 2). 



The inferior vertebral angle is rather more obtuse ' than in the higher forms, i. e. 

 than in Man and Troglodytes. 



The glenoid surface is pyriform (PL XXXV. figs. 4 & 5 ^), with the broad end down- 

 wards, as in Troglodytes ; it is more elongated in proportion to its breadth than in Man, 

 but it is more concave vertically than in the Chimpanzee or Gorilla. 



The coracoid process is shorter and thicker than in Man, and is broadest behind'*, 

 being very much expanded and flattened at the posterior part of its upper surface. Its 

 inclination towards the glenoid surface is much as in the Chimpanzee, and greater 

 than in Man and the Gorilla, but it agi-ees with that of these Apes, and difiers from 

 Man's in being directed more downwards and less forwards (PL XXXV. fig. 2). 



This process is subject to considerable individual variation as to its length'' (PL XXXV. 

 figs. 4 & 5), and as to the presence or absence of a smooth groove in its inner surface'. 



The coracoid is entirely separate from the rest of the scapula when the first true 

 molar of each jaw has come into use*. 



Clamcle. (Plate XXXVII. figs. 1-4.) 



The clavicle of the Orang is much elongated, and both absolutely longer, and longer 

 as compared with the spine, than m Man or Troglodytes. Indeed in the Orang the 



' Archives du Mus. t. viii. p. 24. ^ There is a slight sigmoid curvature in the variety Mo 



' E.g. in the specimen No. 5.5. 12. 20 in the British Museum. 



' Scarcely more so in the variety Jlorio than sometimes in the Gorilla. 



" Also the case in the variety Morio. 



' In the specimen 3 A in the British Museum it is very short, in 30, however, it is much longer. 



' Present in both seapulte of No. 3C in the British M'iseum ; also in the Gorilla No. 1011 I. 



' Such is the case in the specimen No. 3 H in the British Museum. 



riu. 



