204Mr.De la Beche on theGeographicalDistribiition of Organic 



M.Boblaye furnishes us with the following list of the Fossils 

 of the North of France : he considers the Gryphaea Cymbium 

 as most characteristic of the marls and calcareous sands, and 

 the Plicatula echinata of the ferruginous limestones : 



Ammonites Delonchampi, and many others. 



Belemnites trisulcatus (Blainville), and many others. 



Gryphaea arcuata. 



Cymbiiun, 



Plicatula spinosa (Sow). 

 Plagiostoma pectinoides. 

 Pecten (new species). 

 Ostrea. 



Lythodomus. 



Modiola. 



Pinna. 



Encrinites. 



Caryophyllia. 



Turbinolia. 



M, Dufrenoy mentions that near Aubenas a lamellar lime- 

 stone rests on lias, and contains an abundance of Entrochi. 

 He also states, that near Uzer the Ammonites are so abundant 

 as almost to compose the rock : the principal are. 



Ammonites elegans. 



— annulatiis. 



With these are found Terebratula orjiithocepliala, T. ohso- 

 letn, Modiola, and Unio crassissimus. Near Villefranche, mi- 

 caceous argillaceous beds seem to afford a passage of lias into 

 inferior oolite ; they contain Gryphaea obliqua, G. Cymbinm, 

 and Belemnites. 



From the above lists we may construct the following table 

 of organic remains found in more than one of the localities 

 enumerated ; omitting Gryphaea Cymbium, the only fossil of 

 the North of France found in either of the other localities. 



Table 



