THE GREAT CHIMPANZEE. 393 



those processes and there project shghtly, their median coalesced margins being in- 

 chned forwards, and tiius ottering a feature of approximation to the human structure, 

 which is very faintly indicated, if at all, in the skull of the Tr. niger. The nasal bones 

 however subside in the larger species as they expand at their lower halves, where they 

 form a nearly flattened oval disc, terminating in a slight point below, and articulating 

 laterally not only with the maxillary bones, but with an expanded superior portion of 

 the premaxillaries (22')- A considerable extent of the sutures uniting these bones with 

 the maxillaries remains in both the adult male and female skulls of Tr. Gorilla, whilst 

 those sutures are very early obliterated in the Tr. niger. The ninth character, there- 

 fore, by which the Chimpanzee more nearly resembles Man than the Orang does*, 

 applies to the smaller species of TVoglodytes, and not to the genus. 



In the specimen of the skull of an immature Tr. niger, with only the twenty deciduous 

 teeth in place, in the museum of the College of Surgeonsf, the maxillo-premaxillary 

 sutures, still traceable at the sides of the nasal aperture as well as on the palate, show 

 that each premaxillary bone terminates above in a point which does not reach the 

 nasals: in another specimen, a little more advanced, for the inspection of which I am 

 indebted to Mr. Stutchbury, the upper pointed ends of the premaxillaries reach the 

 confluent nasals, and divide their lower extremity from the nasal processes of the max- 

 illaries ; but they do not expand there as in the Tr. Gorilla, and the sutures of the pre- 

 maxillaries disappear in the adult of the Tr. niger\. In all the specimens of the adult Tr. 

 Gorilla a greater or less proportion of the sutures of the premaxillaries remain, and show 

 that the premaxillaries expand at their upper extremities and form a triangular plate of 

 bone on the outer surface of the face which ascends, above the bony nostril, upon the 

 sides of the lower half of the lower expanded part of the confluent nasals, separating 

 that part from the maxillary bones, and excluding the maxillaries from the periphery 

 of the external nostril. This character of the premaxillaries is constant in three skulls 

 of the Tr. Gorilla first transmitted by Mr. Stutchbury, and in two others which he 

 has subsequently sent ; and I regard it as decisive of the specific distinction of the Tr. 

 Gorilla. 



The inferior or alveolar part of the premaxillaries, on the other hand, is shorter and 

 less prominent in Tr. Gorilla than in Tr. niger, and in that respect the larger species 

 deviates less fi-om Man. The anterior surface of the premaxillaries is more irregular or 

 undulated by the prominent sockets of the incisors in Tr. niger than in Tr. Gorilla. The 

 nostril is a wider and more regular ellipse in Tr. Gorilla ; it is contracted above in Tr. 



* Zool. Trans, vol. i. p. 3G8. 



t This is the specimen alluded to by Mr. Lawrence when treating of the intermaxillary bone in the fourth 

 chapter of his " Lectures on the Natural History of Man," 8vo, 1819, p. 174. 



I M. de Blainville, describing the skull of the Chimpanzee from a young specimen of the TV. niger, says, 

 " Mais les prcmaxillaires, qui offrent la particularite de toucher a peine les os du nez et de sender de fort bon 

 heure avec les maxillaires." (Ostcographie, fasc. i. p. 33.) 



