SECOND TERTIARY PERIOD. 



483. Independently of several hundred species of Vertebrata 

 and Annulata, the fauna of this period included 1576 species of 

 Mollusca and Radiata, which have been enumerated and described 

 by D'Orbigny. 



484. A great number of new animals abounded in the seas, the 

 chief part of which consisted of^new genera of fishes and Poly- 

 paria or Zoophytes. It was in this period that the class of Cetacea 

 or marine mammifers first appeared in the geneia oi the Dolphin 

 and the Balcenodon. Among the Crustacea the generic forms of 

 crabs were first presented. 



485. Of the Zoophytes and Foraminifera, the Miliola3, charac- 

 terised by its multilocular shell, and taking its name from milium, 

 the Latin word for millet seed, prevailed in numbers so enormous, 

 as to f.rm those strata of stoire of which nearly the whole of the 

 city of Paris is built. It is a curious circumstance, therefore, that 

 one of the greatest cities of the world should owe its fabrication to 

 the original industry of minute animals which lived countless ages 

 before the creation of man. The prodigious multitude of these 

 minute beings, which must have existed to produce the quarries of 

 Paris alone, not to mention similar ones which exist elsewhere, may 

 be imagined when it is stated that, taking into account the weight of 

 these shells, it has been calculated that a cubic inch of stone must 

 be composed of not less than two thousand millions of them. 



486. The marine flora of this period was generically similar to 

 that of the last, differing, however, altogether in the species. 

 Numerous land animals appeared for the first time, among which 

 may be mentioned the following, mammifers, apes and bats ; 

 birds (fig. 188), predaceous climbers and gallinaceous ; reptiles, 



Fig. 188. Fossil in the Gypsum of Montmam-e. 



127 



