THEIR FLORA. AND FAUNA. 207 



be characterised by its own peculiar plants, and these for the 

 most part having a general relationship to the existing vege- 

 tation of the same regions. It must be admitted, however, 

 that the flora of all the tertiaries lower, middle, and upper 

 requires much more minute botanical investigation ; and 

 till this is done, geologists can offer little more than mere 

 approximations to the conditions of the period. 



Like the flora, the fauna of the lower tertiaries would 

 seem to imply the existence of genial conditions at once of 

 climate, food, and habitat. Gigantic sharks, turtles, cro- 

 codiles, and sea-serpents in the basins of London, Paris, and 

 the Ehine, indicate much warmer waters than these lati- 

 tudes now enjoy ; while elephantine, tapir-like, camel-like, 

 lion-like, and ape-like forms among their terrestrial fauna 

 point unmistakably to sub-tropical or tropical surroundings. 

 NOT is it mere variety of generic and specific forms among 

 these mammalia, but their huge size and vast numerical 

 abundance, that point in the same manner to favourable 

 conditions of existence. Indeed, one of the most remark- 

 able features in the life of the period is the vast bulk of 

 the mammalia as compared with the same orders still exist- 

 ing. This massiveness of structure runs throughout all the 

 divisions of the system lower, middle, and upper and 

 marks alike the tertiary fauna of Europe, Asia, America, 

 and Australia. If the number and magnitude of reptilian 

 forms that thronged the secondary waters have conferred 

 on that cycle the designation of " The Age of Beptiles," 

 the number and magnitude of mammalian forms that peo- 

 pled the tertiary lands may in like manner entitle this 

 period to be signalised as "The Age of Mammals." Pdlce- 

 otheres, or tapir-like beasts, huge as elephants ; sivatheres, 

 or antelope-forms, tall as giraffes ; megatheres, or sloths, 

 weightier than the weightiest hippopotamus ; glyptodons, or 

 armadilloes, that could enclose a score of the living species 



