244 LECTURE IX. 



support existence in the noi'tliern regions. It seems remark- 

 able tliat an elephantine species, the mastodon, which in the 

 alluvial formations of North America replaces the elephant, 

 is also represented in Europe by a species {Mastodon angusti- 

 dens) which appears in the old layers of the tertiary period. 



We shall presently have to examine whether these various 

 species, which, excepting the mastodon, resemble the present 

 living species, have become extinct at the same period. 



All other species hitherto found in caves and the alluvium, 

 agree with the existing, excepting in size, which seems to 

 increase in the older bones. It has, however, been justly 

 observed, that this character is insufficient for the distinction of 

 species, as it frequently depends on the abundance of food, and 

 facility of procuring it. One of the bear skulls found at the 

 Stoss, far exceeds in dimensions any of the brown bear recently 

 found ; yet, in the bear menagerie of Berne, they have, accord- 

 ing to Riltimeyer, broug-ht up bears which attained an equally 

 colossal size, Pictet seems, therefore, perfectly justified in 

 declining to assume difierence of species from the mere size 

 of the fossil bones. On examining the list of bones hither- 

 to found, we observe that almost all mammals of the present 

 fauna of Europe, excepting some few and not easily to be 

 distinguished species, or manifestly imported domestic animals, 

 were represented in the diluvial period, so that the fauna of 

 Europe was richer then than it is now. Pictet enumerates all 

 these species, and shows that but a few small species are want- 

 ing, and that, even recently, species, such as the porcupine and 

 the moufflon, the ancestor of our domestic sheep, have been 

 discovered in Italy. There can, therefore, be no doubt, that 

 most living species existed in the diluvial period ; though it is 

 going too far to deduce from this that no new creation or 

 origin of species had occurred within or since the diluvial 

 period. In the same way as the extinct species disappeared 

 at different periods, so may the present existing species have 

 arisen at different times, though within the same great epoch. 



As regards Hvin^ species, the remains of which are also 

 found in the caves and alluvial mountains of central Europe, 

 there is, again, found a difference, in so far as many of these 

 species have changed their habitat, and have entirely withdrawn 



