﻿ELEPHAS ANTIQUUS— DENTITION. 



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Long Hole (1), Minchin Hole, Raven's Cliff, Spritsail Tor (1) in Glamorganshire 

 (Falconer) ; DurdhamDown (1) in Somersetshire (Falconer) ; Portland Fissure, in Dorset- 

 shire (Busk) ; Castletown Bone Caves, Staffordshire (Dawkins). 



II.— DENTITION. 



The classification of Elephants, founded on the number of laminae and the relative 

 proportions and structure of the enamel, dentine, and cement, has received valuable 

 exponents in the divisions instituted by Falconer into the sub-genera Stegodon, Loxodon, 

 and Eulephas ; moreover, believing in the persistency and uniformity of the characters of 

 molar teeth through seemingly vast intervals of time as displayed in the Mammoth, 1 he 

 formulated the colliculi in the successive teeth, and maintained their specific constancy 

 within a moderate range of individual variation. He did not admit intermediate forms, 

 and therefore viewed the dentition as broadly distinctive of species. It seems to me, 

 after a critical examination of the dental materials of Proboscidea, that a rigorous 

 adherence to numerical formulas as regards the molars of Elephants in general and 

 ffleplias antiquus in particular as established by Dr. Falconer is incompatible with the 

 results furnished by a close analysis of abundant specimens ; indeed, as regards the very 

 variable characters of the molars of the Elephant under consideration, it will be evident 

 that they present very close affinities in all available characters to other teeth at present 

 considered as belonging to distinct species, and consequently the susceptibility of mutation 

 must be considered as an important etiological fact in the genesis of the species. 



In estimating the number of ridges entering into the composition of a molar it has 

 been the habit with several observers to eliminate the talon ridges, and only include the 

 laminae which arise from the common base. Now, as the proximal and distal ridges 

 vary very much in size and configuration, it is apparent that the rejection of any single 

 ridge however dwarfed or insignificant must greatly interfere with the accuracy of a 

 ridge formula established from a large assortment of materials. I have, therefore, 

 in the following included talon ridges at all worthy of the name, whether arising from 

 the common base or from a plate. 2 



1. INCISORS. 



I can find no reference anywhere to the milk incisor of Eleplias antiquus either in 

 museums or in published accounts. It seems to be unknown. Whether, therefore, like the 



1 Essay on the American fossil Elephant, 'Pal. Memoirs,' vol. ii, p. 252; also 'Natural History 

 Eeview ' for January, 1863. 



2 In giving the ridge formula I have carried out the method adopted by Dr. Falconer and others of 

 making "a" represent the talon. 



