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those bones with the maxillaries in the gorilla and chimpanzee, to 

 the part of the upper jaw containing the incisive teeth, on the 

 development of which depends the prognathic or brutish character 

 of a skull. Now the extent of the premaxillaries below the nostril 

 is not only relatively but absolutely less in the gorilla, and con- 

 sequently the profile of the skull is less convex at this part, or less 

 ' prognathic,' than in the chimpanzee. Notwithstanding the degree 

 in which the skull of the gorilla surpasses in size that of the chim- 

 panzee, especially when the two are compared on a front view, the 

 breadth of the premaxillaries and of the four incisive teeth is the 

 same in both. In the relative degree, therefore, in which these 

 bones are smaller than in the chimpanzee, the gorilla, in this most 

 important character, comes nearer to man. In the gibbons the 

 incisors are relatively smaller than in the gorilla, but the pre- 

 maxillaries bear the same proportional size, in the adult male 

 siamang. 



Next, as regards the nasal bones. In the chimpanzee, as in the 

 orangs and gibbons, they are as flat to the face as in any of the 

 lower Simice. In the gorilla, the median coalesced margins of the 

 upper half of the nasal bones are produced forwards ; in a slight 

 degree it is true, but affording a most significant evidence of 

 nearer resemblance to man. In the same degree they impress 

 that anthropic feature upon the face of the living gorilla. In some 

 pig-faced baboons there are ridges and prominences in the naso- 

 facial part of the skull ; but they do not -really affect the question 

 as between the gorilla and chimpanzee. All naturalists know that 

 the semnopitheques of Borneo have long noses ; but the proboscidi- 

 form appendage which gives so ludicrous a mask to those monkeys 

 is scarcely the homologue of the human nose, and is unaccompanied 

 by any such modification of the nose-bones as gives the true 

 anthropoid character to the human skull, and to which only the 

 gorilla, in the ape tribe, makes any approximation. 



No orang, chimpanzee, or gibbon shews any rudiment of mas- 

 toid processes; but they are present in the gorilla, smaller indeed 

 than in man, but unmistakeable ; they are, as in man, cellular, and 

 with a thin outer plate of bone. This fact led me to express, 

 when in respect to the gorilla, only the skull had reached me, the 

 following inference, viz. : ' from the nearer approach which the 

 gorilla makes to man in comparison with the chimpanzee, or orang, 

 in regard to the mastoid processes, that it assumed more nearly 

 and more habitually the upright attitude than those inferior anthro- 



