PERSISTENCE OF CHARACTERS. 253 



revolution more sudden and pronounced, or more important 

 in its results, than the intercalation and subsequent dis- 

 appearance of the Glacial period. Yet the ' dicyclotherian ' 

 Mammoth lived before it, and passed through the ordeal of 

 all the hard extremities which it involved, bearing his organs 

 of locomotion and digestion all but unchanged. 



Taking the group of the four European fossil species above 

 enumerated, do they show any signs, in the successive 

 deposits, of a transition from the one form into the other ? 

 Here again, the result of my observation, in so far as it has 

 extended over the European area, is, that the specific cha- 

 racters of the molars are constant in each, within a moderate 

 range of variation, and that we nowhere meet with inter- 

 mediate forms. The specific difference in the molars, be it 

 observed, rests upon a much more deep-seated foundation 

 than the superficial indication, merely, of ' thick-' and ' thin- 

 plated ' varieties. This I shall endeavour to explain with 

 the help of figures. Taking Mastodon Ohioticus at one end 

 of the chain, and E. primigenius at the other, the number of 

 ridges in the last milk meiar and in the three consecutive true 

 molars yields, in the former, the ciphers 3 : 3, 3, 4 ; while 

 in the latter, they rise to 12 : 12, 16, 24. The groups of 

 forms interposed between these extremes yield intermediate 

 numerical formulEe, which are very constant in each species, 

 within a moderate range of individual variation. Thus, the 

 Mastodon Arvernensis gives 4 : 4, 4, 5 ; Elephas (Lox.) meri- 

 dionalis, 8 : 8, 9, 12 ; E. (Lox.) Africanus, 7 : 7, 8, 10-11 ; 

 E. antiquus, 10 : 10, 12, 16. We nowhere find in the suc- 

 successive deposits in Europe, indications of a transition 

 from E. meridionalis to E. antiquus, which could be repre- 

 sented by a formula between 8 : 8, 9, 12 ; and 10 : 10, 12, 16 ; 

 nor between the latter species and E. primigenius by a 

 formula intermediate to 10 : 10, 12, 16, and 12 : 12, 16, 24. 

 The difference is so great, that the penultimate upper true 

 molar (m. 2), which in E. meridionalis does not exceed 9 

 ridges, attains in the Mammoth 16. And it is further to be 

 borne in mind, that these numerical distinctions in the divi- 

 sions of the crowns of the molars are accompanied by other 

 specific characters which are equally constant. 



The inferences which I draw from these facts are not 

 opposed to one of the leading propositions of Darwin's theory. 

 With him I have no faith in the opinion that the Mammoth 

 and other extinct Elephants made their appearance suddenly, 

 after the type in which their fossil remains are presented to 

 us. The most rational view seems to be, that they are in 

 some shape the modified descendants of earlier progenitors. 

 But if the asserted facts be correct, they seem clearly to 



