13 MAMMALIA. 



kassir, which had no excrescences, were much smaller animals 

 than those which had them and were referred by Wallace to 

 S. morio. 



Wallace does not give any detailed description of the skull 

 of the males he referred to S. morio, but he says, " It is smaller 

 and weaker, and the zygomatic arches narrower than in the 

 large species ; it has no bony crest, but two faint ridges from 

 If inch to 2 inches apart, exactly as in the S. mono of Prof. 

 Owen, figured in the ' Transactions of the Zoological Society.' 

 The teeth, however, are, in proportion to the skull, of immense 

 size, equalling, and in one case surpassing, those of the larger 

 animals; the molars extending further backward, and the 

 incisors and canines being set closely together, room is found 

 for them in a, much smaller jaw.'' The only skulls in this 

 Museum corresponding generally to the foregoing description 

 are those of female Orangs. 



One adult male skull, Zoo, resembling, in size and in the 

 development of its zygomatic and orbital ridges, the skull of 

 the adult 3« with cheek excrescences, differs from it and 

 resembles S. morio in the temporo-parietal ridges being far 

 apart. Although this feature of S. morio occurs in this skull, 

 there can be no doubt of the specific identity of the skull with 

 the individual Sa or with S. satyrus, and Mr. Blyth records 

 that Mr. Nicholls, who presented this Orang to the Asiatic 

 Society of Bengal, stated that, if he remembered rightly, the 

 skeleton had been given to him as that of a male, full 

 grown, but not aged, and with a very broad face — a de- 

 scription which evidently indicates that the animal was an 

 Orang with cheek excrescences. The non-union of the 

 temporo-parietal ridges to form a sagittal ridge would appear 

 in the case of male Orangs to be generally a sign that the 

 animal had not attained full maturity. This skull has all its 

 permanent teeth perfectly fresh and unground, and a few more 

 years of masticating activity would probably have brought 

 the ridges together. Even in female skulls referable to 

 S. morio, the feeble lines indicating the temporal ridges tend 

 to meet on the vertex in the fully adult animal, and in one skull 

 the ridges are only separated by an interval of 0'-40, which, 

 in all likelihood, would have disappeared with increased age ; 

 whereas in a female, with the last molar only cutting the gum, 

 these ridges are 0"-50 apart. At the same time, in some cases, 

 feeble development of the lower jaw, as pointed out by Mr. 

 Wallace, associated with a small zygomatic aperture and a 

 large cranial surface, contributes to keep the temporal ridges 



