304 



EOCENE FORAMINIFERA. 

 Fig. 267. 



Triloculina inflata, Desh. 

 t. Natural size, a, c, d. Same magnified. 



[Ch. XVI 



Clcwulina corrugata, Desh. 

 a. Natural size. &, c. Same magnified. 



" Miliolite limestone." It is almost entirely made up of millions of 

 microscopic shells, of the size of minute grains of sand, which all 

 belong to the class Foraminifera. Figures of some of these are given 

 in the annexed woodcut. As this miliolitic stone never occurs in the 

 Faluns, or Upper Miocene strata of Brittany and Touraine, it often 

 furnishes the geologist with a useful criterion for distinguishing the 

 detached Eocene and Miocene formations scattered over those and 

 other adjoining provinces. The discovery of the remains of Paleo- 

 therium and other mammalia in some of the upper beds of the cal- 

 caire grossier shows that these land animals began to exist before the 

 deposition of the overlying gypseous series had commenced. 



Lower Calcaire grossier, or Glauconie grossiere (B. 1, p. 298). — The 

 lower part of the calcaire grossier, which often contains much green 

 earth, is characterized at Auvers, near Pontoise, to the north of Paris, 

 and still more in the environs of Compiegne, by the abundance of 

 nummulites, consisting chiefly of N. laevigata, JV. scabra, and N. La- 

 marcM, which constitute a large proportion of some of the stony 

 strata, though these same foraminifera are wanting in beds of similar 

 age in the immediate environs of Paris. 



Soissonnais sands, or Lits coquilliers (B. 2, p. 298). — Below the 

 preceding formation, shelly sands are seen, of considerable thickness, 

 especially at Cuisse-Lamotte, near Compiegne, and other localities .in 

 the Soissonnais, about fifty miles N. E. of Paris, from which about 300 

 species of shells have been obtained, many of them common to the 

 calcaire grossier and the BracHesham beds of England, and many 

 peculiar. The Nummulites planulata is very abundant, and the 

 most characteristic shell is the Nerita conoidea, Lam., a fossil which 

 has a very wide geographical range ; for, as M. d'Archiac remarks, 



