THE CHIMPANZEES AND ORANGS. 173 



viduals of the great Orangs {Pith. Satyrus) before they attain old age (' I'age vieux ') : 

 it is not the absolute characteristic of any age of the species. 



In the skull no. 3 B, Brit. Mus., the parietal crest is 3 lines high : the first true 

 molar shows the small cavities on the grinding surface formed by the more prominent 

 pair of cusps of the opposite tooth, upon the inner half of the upper, and on the outer 

 half of the lower tooth. These cavities have hardly begun to be formed on the second 

 molar ; and the grinding surface of the third molar shows its primitive minutely 

 wrinkled surface. In this skull about half an inch of the stylohyal is ossified and 

 anchylosed to the vaginal ridge, forming the so-called ' styloid process ' of the tem- 

 poral bone. 



The skull no. 1080, which by the state of the teeth is about the same age as the 

 preceding, has also a parietal crest 3 lines in height, but it is thicker than in no. 3 B : 

 the styloid processes are 3 lines in length. 



In the skulls nos. 1085 and 1088, the cavities in the second true molars are rather 

 better marked, but the crown of the third molar is wrinkled ; the crowns of the canines 

 are obliquely worn, the upper ones by attrition against the first lower premolars ; but 

 they retain their full length : the incisors have had half the crown abraded. The 

 sagittal crest is similar to the foregoing : there are no styloid processes. The nasal 

 bone is shorter in 1085. 



In an adult male of the large Orang, in Mr. Stevens's charge, no. 2, with less-worn 

 incisors and canines, the parietal ridge is 4 lines high. The nasal bone does not rise 

 above the level of the malo-frontal suture ; it is bisected by the maxillaries meeting 

 at the median line, as in the skull in the Leyden Museum, above noticed'. 



In the skull in the British Museum, no. 3 A, with the canines and incisors much 

 more worn down than in the foregoing skull, and with deep cavities in both the first 

 and second molars, and also in the third molar of the lower jaw, the temporal ridge is 

 less elevated, but is thicker : there is a styloid process on the right side, 5 lines in length. 



In the skull no. 1079, all the molars, as also the premolars, show deep cavities 

 through long attrition, and the crowns of the upper canines are much worn away : the 

 temporal ridge is low and thick, not higher than in the skull no. 3 A. The styloid 

 processes are 5 lines in length. 



The skull no. 3 C (PI. L. fig. 1) is of an aged individual : the inner halves of the 

 upper molars {ib. fig. 2) are worn half-way down. The parietal crest is moderately 

 thick, and 4 lines high. 



In this series of crested skulls there are modifications of general size and proportions, 

 of extent of the molar series, of the shape of the nasal bone, of the size and shape 

 of the orbits, of the degree of prominence of the superorbital ridge, and of the pre- 



' I have seen the skull of an Orang (Pith. Satyrus) in which the nasal bone was reduced to its lower border 

 — a small piece wedged into the upper part of the bony nostrU ; and another skull of an Orang without any 

 trace of nasal bone, the place of which was supplied by the united nasal processes of the maxillaries. 



VOL. IV. — PART V. 2 C 



