PHYLOGENY. 163 



anthropoids. But the posterior face of the symphysis 

 presents the most remarkable pecuharity. In the 

 symphysis of the apes (Fig. 54, A, B, C) the posterior 

 border is a continuous slope from the alveolar border 

 to the inferior margin, interrupted by a shght concav- 

 ity below the middle. In the human jaw this line 

 slopes backward to near the middle, where are situated 

 the small tuberosities for the insertion of the genio- 

 glossal muscles. (B in the accompanying figures.) The 

 surface then slopes rapidly forward to pass into the 

 narrow inferior border of the chin (Fig. 46, F, G). In 

 the jaws Naulette and Spy the structure is exactly in- 

 termediate between the two, and quite different from 

 both (Fig. 45, D, £). It commences above with a pos- 

 terior slope similar to that of the apes, exhibiting 

 what is called by Topinard "internal prognathism," 

 as it appears in the lower human races. The surface 

 then descends abruptly, forming a vertical concavity, 

 which is bounded a considerable distance below by 

 another protuberance, the insertion of the genioglossal 

 muscles. This concavity is not present in the human 

 symphysis, while it is less developed in the simian. 

 The surface then slopes forward, as in the human sym- 

 physis, but this portion is shorter than in human jaws 

 generally. It is represented by a convex face in the 

 simian jaw. This character, taken in connection with 

 the others cited, goes a long way toward justifying the 

 separation of the Neanderthal race as a distant species, 

 as has been done by some author under the name of 

 Homo neanderthalensis. This name is objectionable but 

 must be retained. 



To these observations Messrs. Fraipont and Lohest 

 add the following. 



V. The curvature of the ulna and radius, which 



