THE CHIMPANZEES AND ORANGS. 113 



has nevertheless the usual size and shape of the first vertebra of the ordinary coccyx. 

 The sacrum is consequently longer in proportion to its breadth than in the Esquimaux, 

 and, like the sacrum of most male Europeans, it is larger in all dimensions, with a deeper 

 anterior concavity, than in the Negro or Australian. The so-called transverse processes 

 of the first sacral vertebra slope more downward from the anterior articular surface of 

 the centrum than in the Esquimaux, the direction being more like that in the Australian. 

 The anterior zygapophyses also resemble those of the Australian in being larger and 

 more sessile than in the Esquimaux, and the tuberosity which extends outward and 

 forward from their base is much less produced than in the Esquimaux. The articular 

 surface for the ileum terminates on the same transverse line with the third sacral fora- 

 men, as in the Australian. In the Esquimaux it extends very little beyond the second 

 sacral foramen. In the present sacrum the neural arch is completed over four vertebrae 

 and supports a spine : in the last two sacral vertebrae the neurapophysis coalesces with 

 its homotype of the contiguous vertebra, but not with its fellow in the same vertebra. 



All the differences above noted, after a scrupulously detailed comparison of the bones 

 of the different varieties of the human race, are much less in degree and very inferior in 

 importance to the majority of distinctions established in the present comparison between 

 the skeleton of the lowest varieties of Man, and that of the highest of the Ape tribe'. 



DESCRIPTION OF THE PLATES. 



(All the figures are of the natural size.) 



PLATE XXXI. 



Mandibula or Lower Jaw. 

 Fig. 1. Side view of the lower jaw of an adult male Gorilla (Troglodytes Gorilla). 

 Fig. 2. Side view of the lower jaw of an adult male Austrahan. 

 Fig. 3. Upper view of the lower jaw and teeth of ditto. 

 Fig. 4. Back view of the ascending ramus of the lower jaw of ditto. 



PLATE XXXII. 

 Fig. 1. Upper view of the lower jaw and teeth of the Gorilla. 

 Fig. 2. Back view of the ascending ramus of the lower jaw of ditto. 



' The paragraphs in brackets were added in 1853 to the original Memoir, and communicated, with an exhi- 

 bition of the illustrations of that Memoir, to the Academy of Sciences, Institute of France, September 1853. 

 (See the 'Comptes Rendus,' Sept. 5th, p. 388.) The memoir on the Troglodytes Tschego and Gorilla gina, by 

 my late esteemed friend Prof. Duvernoy, was read to the Academy on the 30th May, 1853, and has been pub- 

 lished in the 'Archives du Museum d'Hist. Nat.' tom. viii. 1855. It was the last of a long series of valuable 

 contributions to his favourite science. 



VOL. IV. PART IV. S 



