2 2 THE EOCENE BEDS 



mon, the latter being especially distinctive. The upper parts of the 

 beds also contain Potamides lapidum and Dissostoma mujiuiiia, 

 with Ampullina parisiensis and Liicina saxorian. 



Pochette. — This bed is often formed of a mass of Corbula 

 anatiiia, together with Anoinia tenuistriata, Aleretrix eiegatis, and 

 Cerithidae, as F. echinoides, P. cristatits and P. lapidum. 



Some of the species above enumerated are particularly found 

 in a brown marine marl, called pain d'epice, * on account of its 

 colour. 



Marls of Nanterre. — This bed, well developed at Nan- 

 terre, is regarded as a chemical precipitate, and is used for 

 wood polishing. In other parts of the basin this horizon is 

 characterised by fragmentary, white, calcareous marls, with 



Fig. 7. — Section of the Calcaire Grossierat the Ecole d' Agriculture., 



Grig nan. 



ft. in. ft. in. 

 f, Vegetable earth and sandy marl . 2 o to 3 o 











oix 



XZI 



H.W.B., 1890. 



Buff - coloured Calcaire Grossier, 



more or less sandy, few fossils .10 oto 12 o 



j Sand with green grains, (?) glau- 



1 conite ....... 



I Buff-coloured, sandy Calcaire Gros- 

 J sier, darker than above, with 



I very varied and well-preserved 



^ fossils . . . . . 3 o to 4 



Yellow, sandy marl with glaii- 



conitic grains . . . 4 o to 5 



vK Bottom of pit. 



THard Calcaire Grossier with beds 



of stone,containing Echinoidea 



i -, in the softer partings, about 



I 6 ft. below bottom of pit, 



1^ occasionally exposed . . about 6 o 



Base not seen. 



* Gingerbread. 



