242 M. Brou GUI ATtT on the 



rocks to the chalk formation, which at first sight appear 

 very different from it. Thus only the two last chalks are 

 seen at Cap de la Have, near Havre, at Honfleur, &c. * 

 This inferior chalk is the same with that observed in Eng- 

 land by De Luc, between Beachy Head and Sea Houses, on 

 the coast of Sussex, and so well described by thatgeologist.t 

 This chalk does not differ from that which Mr. William 

 Phillips has observed to the W. of Calais on the coast of 

 France, between Sangatte and St. Pot ; and which appears 

 to correspond exactly with that of the English coast between 

 Dover and Folkstone. In both these situations, as in many 

 other places, the white chalk and craie tufau are separated 

 from the glauconie craieuse (green sand of the English geo- 

 logists) by a bed of bluish clay marl. J Among the fossil 

 shells which occur in these chalks and which apparently 

 characterize them, I shall mention the following, as coming 

 from the three places I have just noticed, i. e. Rouen, Havre, 

 Honfleur, and even the continuation of this coast to Dives. 



Organic remains of the craie tufau and green sand (glau- 

 conie craieuse) of Rouen, Havre, Honfleur, the environs of 

 Dives, &e. 



Nautilus simplex . . . Sow : Rouen. 



Scaphites obliquus. .Sow : (pi. viii. fig. 4.) || . . . Rouen, Brighton. 



o CRouen.Havre.whereit 



Ammonites varians .Sow: |^^^^^^ „f ^ ,^^g^ ^-^^^ 



inflatus.. Sow: Havre. 



(Rouen, it acquires the 

 rothomagensis.Defr: (pi. vi. fig. 2.) •? size of more than a de- 



(cimetre. 



* I have myself observed the structure of the hill of St. Catherine, and 

 ofthe cliffs from Honfleur to Dives ; but I am indebted to M. St. Brice 

 for a great part of the shells from the former place. All I know con- 

 cerning the structure of Cap la Heve I owe to M. Audouin. 

 f Geological letters to Blumenbach, p. 200. 

 ^ Transactions of the Geological Society. 



11 The Plates quoted in parentheses are those of the new edit! on o? 

 the Description geologique des environs de Paris, iu which part of 

 this memoir is inserted. 



The initials Defr. represent Defrance. 



A. Br A Brongnian 



Sow. Sowerby. 



Lam Lamark. 



