382 PROFESSOR OWEN ON THE OSTEOLOGY OF 



least of a closely allied species." This Pongo Cuvier also affirmed to be the largest and 

 most redoubtable of the Apes, as, in fact, it was in comparison with the species known 

 at that time. 



Believing the characters of the young Orang to be those of the genus, Cuvier places 

 the Chimpanzee, although he knew it also from immature examples only, below the 

 Orang, on account of the absence of the forehead, the cranium receding immediately 

 behind the supraciliary ridge*. 



It was obvious, therefore, that in order to a clear understanding of the zoological 

 relations of the highest of the brute creation to each other as well as to Man, the 

 characters of the full-grown and mature individuals of the Orang and Chimpanzee 

 required to be determined ; and to this jioint I devoted some of my earUest investiga- 

 tions into Comparative Anatomy. In the memoir "On the Osteology of the Chim- 

 panzee and Ourang-Utan," published in the first volume of the ' Zoological Transactions' 

 (p. 343), the great Ape to which Cuvier refers under the name of ' Pongo' was proved, 

 by the comparison of its teeth with the germs of the permanent teeth in the skull of the 

 type of the species called ' Orang-outang' by Cuvier, to be the adult of that supposed 

 anthropoid species. 



In my inquiries and researches after specimens which might throw corresponding 

 light on the true nature of the Chimpanzee, I was unexpectedly gratified by finding that 

 there existed in the private collection of a surgeon in London (the late Mr. Walker of 

 St. George's Hospital) — unknown apparently to the naturalists and anatomists of the 

 metropolis — the complete skeleton of an adult female Chimpanzee {Troglodytes niger, 

 Geoft".). This specimen yielded the true cranial and other osteological characters of 

 Cuvier's second species of Anthropoid Apef; and, allowing for sexual distinction, it 

 showed a retrogradation to the brute or baboon-like character in the Chimpanzee during 

 its progress to maturity, analogous to that which had been proved to take place in the 

 true Orang-utan (Pithecus). 



The comparison of the adult Chimpanzee [Troglodytes niger) with the adult Orang 

 {Pithecus Satyrus) also showed that the superior development of the forehead upon which 

 Cuvier had relied in determining the relations of the Orang with Man was more appa- 

 rent than real, and that the more immediate backward slope of the forehead in the Chim- 

 panzee was due principally to the characteristic prominence of the thick supraorbital 

 ridge. Sixteen characters were adduced in the memoir above cited (p. 3G9) by which 

 the Chimpanzee in difiering from the Orang approached nearer to Man, whilst only three 

 equivalent characters of closer correspondence to Man were demonstrated in the Orang ; 

 whence it was inferred that the Chimpanzee ought to rank above the Orang and next 

 to Mant, a conclusion which was adopted by M. de Blainville in his ' Osteographies,' 



* Regne Animal, Svo, Paris, vol. i. p. 89. 1829. 



t Zool. Trans, vol. i. p. 343, pis. 48, 50, 51 & 52. 



J Zool. Trans, vol. i. p. 369. § Fasc. i. p. 32. 



