91 



October 25, 1836. 

 Dr. Bostock in the Chair. 



Two skulls of the Orang-Utan of Borneo, and a skin, including 

 the cranium, of an immature Orang-Utan of Sumatra, were exhibited. 

 They were transmitted to England by Dr, W. Montgomerie of Sin- 

 gapore, with a statement that the young Sumatran Orang had died 

 in that gentleman's possession soon after having acquired additional 

 grinders. 



Mr. Owen availed himself of the occasion to make the following 

 observations on each of the above specimens. 



He stated that the skin of the young Sumatran Orang agreed in 

 the rufous colour, texture, disposition, and direction of the hair, with 

 the adult female Sumatran Orang, presented to the Zoological So- 

 ciety by Sir Stamford Raffles ; like that specimen also, it had no 

 nail on the hallvuc or thumb of the hinder hands. The posterior 

 molares on each side of each jaw correspond to the first permanent 

 molares of the adult ; the rest of the teeth consisted of the 8 deci- 

 duous bicuspides, the 4 small deciduous canini, and the 8 decidu- 

 ous incisores. This state of the dentition was similar to that of the 

 human child at the 7th year ; but it would be unsafe to infer from 

 this circumstance that the age of the Orang corresponded : it being 

 more probable, from the characteristic duration of the immature 

 state in the human species, that the shedding of the teeth takes 

 place at a later period than in the Orang. 



Of the two crania of the Bornean Orangs, one differed materially 

 from the other in size and in the development of the cranial ridges. 

 The larger specimen before the Society, closely resembled the cra- 

 nium of the Bornean Pongo or adult Orang in the Museum of the 

 College of Surgeons, and differed, in precisely the same respects as 

 that specimen, from the cranium of the Pongo (supposed to be Su- 

 matran) in the possession of Mr. Cross, described and figured in the 

 1st volume of the Society's Transactions, (p. 380. PI. 53), which 

 induced Mr. Owen to entertain more strongly his original suspicion, 

 .that that cranium belonged to an Orang specifically distinct from the 

 great Bornean species (Simia Wurmbii, Fischer). With respect to 

 the differences alluded to, he stated that the cranium of the great 

 Bornean Orang was characterized by the more oblique plane of the 

 orbits, and consequently the straightness of the contour of the skull 

 between the forehead or glabella and the incisor teeth .: the external 

 boundaries of the orbit were broad and had a rough irregular surface, 

 probably in consequence of the development of the callous protube- 

 rances which characterize the aides of the face in the adult males of 

 this species. The symphysis of the lower jaw was also proportion- 

 ally deeper than in the (supposed) Sumatran Pongo. The cranium 



