350 ILLUSTRATED ZOOLOGICAL NOTICES. 



therefore probable that as the sea encroached upon the land, 

 these remains, by the gradual falling away of the cliffs, be- 

 came engulphed, and are now found at the spots where they 

 were in the first instance deposited, although the level which 

 they now occupy is necessarily somewhat lower. 



Little or nothing has been added by subsequent writers to 

 the description which the illustrious Cuvier has given us of 

 the osteological peculiarities which serve to distinguish the 

 fossil species of the genus Elephas ; and paleontologists 

 still follow him in referring elephantine remains, in whatever 

 region they may be found, to one and the same species. A 

 slighter amount of divergence in the horizontal rami of the 

 lower jaw, accompanied with a change in the shape of the 

 canal formed by the approximation of these parts, especially 

 at its anterior termination ; — grinding teeth wider in propor- 

 tion to their length, and with more numerous and less fes- 

 tooned lamina; — are points of distinction referred to by the 

 above-named distinguished anatomist, when comparing the 

 skeleton of the mammoth with that of the Asiatic elephant, 

 the nearest allied of the two existing species. Mr. Sowerby's 

 drawing admirably displays the form of the anterior termina- 

 tion of the canal in the present specimen. It is not nearly so 

 wide as seen in the figures which illustrate Cuvier's observa- 

 tions, but at the same time it differs materially from that of 

 the existing species, which, in the adult skeleton, has more 

 the character of a deep cleft. A short distance from the sym- 

 physis the canal contracts to about two-thirds the diame- 

 ter of its anterior termination, and a somewhat similar con- 

 traction is shown in one of the jaws figured in the 'Ossemens 

 Fossiles.' The following dimensions may perhaps as well be 

 recorded. 



FT. IN. 



Width between the ascending rami at the coronoid processes, ... 1 7 

 Width of each ascending ramus, measured midway between the 



angle of the jaw and the condyloid apophysis, 1 



Width of canal at the anterior termination, „ 3£ 



Ditto ditto five inches from the symphysis, „ 2| 



Circumference of the symphysis measured from before to behind, 



including the process of the mentum (one inch in length) 1 1 



From the above dimensions it appears that the diameter of 

 the anterior termination of the canal, as compared with the 

 expansion of the ascending rami, is in the proportion of 1 to 

 6 : in the two lower jaws figured in pi. 5 tome i. of the Osse- 

 mens Fossiles, this proportion is represented as 1 to 4. 



I have remarked an extraordinary disproportion in the re- 

 lative number of plates, when fossil elephants' teeth from 

 North America are compared with teeth from the coast of 



