252 SPAEKS FROM A GEOLOGIST'S HAMMER. 



that the primeval mammoths, which, were contemporary 

 with the oldest men in Europe, were the survivors of 

 those encased in Siberian ice. 



I must now allude to some facts of extraordinary in- 

 terest. There were once living in India, but before the 

 period of the primeval mammoth, proboscidians which were 

 intermediate between the mastodon and the elephant in 

 the structure of their grinders. We know a gradation 

 of at least four connecting links. First, there was the 

 wide-toothed mastodon (Mastodon latidens), which had the 

 ridges across the crown (corresponding to the unworn, 

 flattened cylinders of the elephant), more numerous than 

 in the American mastodon, less distant, more tuberculated, 

 with the intervals between them deeper. Secondly, there 

 was the elephantoid mastodon (Mastodon elephantoides\ 

 which had a molar twelve inches long, with ten trans- 

 verse ridges ; in both respects resembling the elephant, 

 but still, unlike the elephant, having very little cenicntinn 

 between the ridges. Thirdly, there was the flat-faced ele- 

 phant (Eleplias planifrons), which, though styled an ele- 

 phant, and having a supply of cementum between the 

 transverse plates, was nevertheless mastodon-like in the 

 shallowness of the clefts between the plates. Fourthly, 

 there was the Hysudric elephant (Eleplias Hysudricus), in 

 which the divergence from the mastodon type was car- 

 ried still farther. But lastly, it is can-ied farthest of all 

 in the living Indian elephant, which has the most com- 

 plex molars found among existing animals. Now all these 

 proboscidians, together with the primeval mammoth, dwelt 

 in successive periods upon the same continent ; and it is 

 a fair inquiry whether they were genealogically related 

 to each other. Venturing to arrange them in a linear 



