of an Orang Otang. 475 



same diameter is 1? lines and a half, it is no less than 7 lines and a 

 half, or nearly equal to otie-half the breadtli of the orbit. Neither 

 is the orbit itself in these animals placed on the same plane ; but 

 while almost vertical in the Satyr us, it forms in the Ponoo an 

 angle with the horizon of many degrees less. These then appear 

 to be some of the most important distinctions. In their absence, 

 indeed, the many others which exist in the form of the skull of 

 these animals might be attributable to age ; for although those 

 of the Satyrus seen in Europe have the skull round and smooth, 

 and the facial angle large (as is so well exemplified in the skele- 

 tons at the Royal Institution, Mr. Brookes's, and at the College 

 of Surgeons), while in the Pongo the skull is angular, provided 

 with sharp ridges or crests, and the facial angle much smaller, 

 such differences, though less apparent, are seen between the 

 young and old of most other quadrupeds. 



In addition to other arguments mentioned in fîivour of the 

 identity of the two animals, the French naturalists assert that tiie 

 vertebrae of each kind are the same in number. This conclu- 

 sion they seem to draw from the large skeleton of the Pongo 

 in the collection of Comparative Anatomy at Paris, but which, 

 being obviously imperfect in several of its parts, I am much 

 inclined to consider is deficient in one of its lumbar vertebra;. 

 They then state all the proportions of the body and limbs to be 

 similar, each to be destitute of the hinder thumb-nail ; each to 

 have large cavities communicating with -the larynx, and of the 

 same form ; neither to possess callosities ; and that the colour 

 differs only in being darker in the Pongo, as we see it in most 

 adult animals. We also know that they inhabit the same coun- 

 try. To these arguments I may with justice add, that the adult 

 Simia Satyriis, as distinct from the Pongo, has never been accu- 

 rately described ; and that the Simia Sati/nm seen here is evi- 

 dently the young of a large species, as is determined by the 



loose 



