1855.] Proceedings of the Asiatic Society. 469 



Report of Curator, Zoological Department, for July, 1855. 



1 . The first contribution which I have now the pleasure of bringing 

 to notice is that of two fine (and nearly perfect) skeletons of the Mias 

 Rambi Orang-utan (Pithecus Brookei, nobis, J. A. S. XX, 375) ; pre- 

 sented to the Society by Sir James Brooke, K. C. B v Governor of Sarawak. 



The skeletons are those of a fully adult but not aged female, with 

 the epiphyses of the limb-bones well anchylosed, yet with sagittal crest 

 undeveloped, — and of a nearly full-grown male, with incipient sagittal 

 crest, but with the epiphyses of the limb-bones more or less detached 

 and exhibiting other proofs of incomplete growth. In both specimens, 

 the third or last permanent grinders had been brought into wear ; the 

 amount of attrition being considerable in the female, and much less so in 

 the male. 



As from the structure of the pelvis and certain other characters, no 

 doubt whatever can exist respecting the sexes of these two individuals, 

 we accordingly obtain the requisite data for deciding upon the sex of the 

 skeleton of an adult Mias Pappan which was presented on a former occa- 

 sion to the Society; and can now pronounce, with confidence, that the 

 latter was a male animal, and moreover it appears from accumulating 

 evidence that the Mias Pappan is a smaller animal than the Mias Rambi, 

 the adult female of the former corresponding in size with the adult male 

 of the latter; the male of the Rambi (to judge from its skull) being 

 much larger. 



Individuals, however, of each may vary in size ; as the skull of the 

 female Rambi now sent is considerably larger than that of the much 

 older female Rambi, with high sagittal crest, figured in plates 3 and 4 

 attached to the memoir upon this genus in J. A. S. Vol. XXII. A distin- 

 guishing sexual feature would appear to exist in the conspicuously greater 

 breadth of the orbital ring exteriorly (especially its malar portion) in the 

 male, and also the greater breadth of muzzle in the adolescent male, and 

 the general appearance of massiveness, indicative of its future growth, 

 as compared with the skull of an adult female. In our huge old Sumatran 

 male, the extent of grinding surface of the series of upper molars (includ- 

 ing bicuspids) is 2£ in.; in the young Bornean male now sent, 2 X % in.: 

 the anterior bicuspid of the latter being somewhat pushed forward outside 

 of the hind margin of the canine, and the interspace between the 

 cauine and outer incisor being but half as great as in the fully developed 

 animal. In both females, the same grinding surface is but 2£ in. ; and in 

 the adult male Pappan, intermediate, or 2\ in. This male Pappan (as 



3 p 2 



