Zoological Characters in Geologi/. 247 



This rock appearing from its position altogether foreign 

 from that which principally occupies me, it will sufl&ce to 

 notice these shells by a name and a figure, so that we may 

 possess the means of describing these diaracteristic shells ; 

 but it is my intention to unite the history of their association, 

 and their description, with that of the shells which belong 

 to the Jura limestone, and which will be the subject of 

 another work. 



The organic remains which I shall content myself by no- 

 ticing in this memoir as characterizing this formation in the 

 Jura^ and many other places, are the following : 



Strombus Pelagi . . 



A.Br. 



(pi. 8ofth 

 fig. 1. A, 



is work* 

 B.C.).. 



The Perte du Rhone. 



Oceani A. Br. (ib. fig. 2. A. B.). - 



'■ Ponti , 



Cardium Protei . . . . 



Hemicardiam tuber- 

 culatum , 



Mya ? or Lutraria ? 

 JuraBsi 



Donacites Saussuri 

 Alduini 



A.Br. 

 A. Br. 



(ib. fis. 3. 

 (ib. fig. 7. 



B.). 

 B.). 



\ A.Br. (ib. fig. 8. A. B.) . 



In an argillaceous 

 marl absolutely the 

 same as to colour & 

 position, at Cap la 

 Heve near Havre, & 

 in the Jura. 

 With the preceding. 

 In the same places. 



In an argillaceous 



marl at Cap de St. 



Hospice near Nice, & 



at the Perte duRhdne. 



In the marls of the 



Perte du Rhone, and 



in the upper oolitic 



or compact limestone 



? A. Br. (ib. fig. 4. A. B.) . i of theJura; of Ligny, 



J I dep'. of the Meuse ; 



of Soulaine, dep'. of 

 tbeAube; ofGondre- 

 _ville,nearNancy,&c. 

 The Perte du Rhone. 

 Cap la Heve. 



(From the Perte du 

 Rhone & the argilla- 

 ceous marls of the 

 same position which 

 are behind the town 

 Lof Neufchatel. 



A. Br. 

 A.Br. 



(ib. fig. 5. 



(ib. fig. e. 



A. B.) . 

 A.B.), 



The greater part of these shells are interior casts, but 

 which have very well preserved their forms and character- 

 istic salient parts, so that they may be determined with 



