MAMMALIA ABUNDANT. 



pachydermatous, and the tapir type continues to be con- 

 spicuous. One animal of this kind, called the di?iotherium 9 

 is supposed to have been not less than eighteen feet long; 

 it had a mole-like form of the shoulder blade, conferring 

 the power of digging for food, and a couple of tusk9 turn- 

 ing down from the lower jaw, by which it could have at- 

 tached itself, like the walrus, to a shore or bank, while 

 its body floated in the water. Dr. Buckland considers 

 this and some similar miocene animals, as adapted for a 

 semi-aquatic life, in a region where lakes abounded. Be- 

 sides the tapirs, we have in this era animals allied to the 

 glutton, the bear, the dog the horse, the hog, and, lastly 

 several felinae (creatures of which the lion is the type 

 all of which are new forms, as far as we know. There 

 was also an abundance of marine mammalia, seals, dol- 

 phins, lamantins, walruses, and whales, none of which 

 had previously appeared. 



PLIOCENE SITB^PERIOD* 



The shells of the older pliocene give from thirty-five to 

 fifty ; those of the newer, from ninety to ninety-five per 

 cent, of existing species. The pachydermata of the pre- 

 ceding era now disappear, and are replaced by others be- 

 longing to still existing families-^-elephant, hippopotamus, 

 rhinoceros — though now extinct as species. Some of 

 these are startling, from their enormous magnitude. The 

 great mastodon, whose remains are found in abundance in 

 America, was a species of elephant, judged from peculia* 

 rities of its teeth, to have lived on aquatic plants, and 

 reaching the height of twelve feet. The mammoth was 

 another elephant, but supposed to have survived till com- 

 paratively recent times as a specimen, in all respects entire* 

 was found in 1801, preserved in ice, in Siberia. We are 

 more surprised by finding such gigantic proportions in an 

 animal called the megatherium, which ranks in an order 

 now assuming much humbler forms— the edentata— to 

 which the sloth, ant-eater, and armadillo belong. The 

 megatherium had a skeleton of enormous solidity, with 

 an armor-clad body, and five toes, terminating in huge 

 claws, wherewith to grasp the branches, from which, like 

 its existing congener, the sloth, it derived its food. The 

 megalonyx was a similar animal, only somewhat less than 

 the preceding Finally, the pliocene gives us for the 



