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XLII. Observations on a Conimunicatio7i made by Dr. Fitton 

 to the Geological Society of France at the Meeting of May 20, 

 1844, on the Lower Greensand of the hie of Wight, By 

 Prof. A. Leymerie*. 

 T T will be imagined, that having investigated in a very espe- 

 -^ cial planner the chalk formation of Champagne, I could 

 not remaui indifferent to the discovery recently made in En- 

 gland, at the base of the Greensand, of strata containing a cer- 

 tain number of Neocomian fossils of the east of France. I took 

 a lively interest in the communications upon this subject, both 

 in the Proceedings of the Geological Society of London, which 

 have been obligingly communicated to me by Dr. Fitton f, and 

 in the Bulletin de la Societe Geologique de France (vol. i. of the 

 second series, p. 438). 



The principal object of this note is to express my opinion 

 on the relations which may connect these new strata with the 

 Neocomian formation of the continent. However, it seems to 

 me indispensable, before coming to this, to cast a critical glance 

 on the list of species which Dr. Fitton considers as being com- 

 mon tothegreensand of England and the Neocomian formation 

 of France, and to show that several species which M.Deshayes 

 and myself have established, are there isrongly represented as 

 related to types formerly known by Sowerby and Nilson. 



The contested species in question are given in the following 

 list, in which I have placed opposite to each other our names 

 and those which Mr. Edward Forbes has substituted for them. 



Names given by MM. Deshayes Corresponding names given by Sow- 



" -■' ^ erby and by IN lison, according to 



Mr. Edward Forbes. 

 Mya plicata, Sow. 

 Astarte obovata. Sow. 

 Cardium striatnhim, Sow. 

 A7'ca exaltata, Nilson. 

 Modiola aqualis, Sow. 

 Pinna tetragona, Sow. 

 Pecten obliqtms. Sow. 

 Natica rotundata. Sow. 



and Leymerie. 



Pholadomya PrexioUi, Desh. 

 Astarte Beaumontii, Leym. 

 Cardium subhillanum, Leym. 

 Cucidlcjea Gabriclis, Leym. 

 Modiola Archiaci, Leym. 

 Pinna sulcifera, Desh. 

 Pecten iiiterstriatuSf Leym. 

 Ampidlaria Icevigata, Desh. 



Having submitted these species to a new examination, and 

 having again compared them carefully, under the eyes of 

 M. Deshayes, with the types to which Mr. Forbes has referred 

 them, 1 believe I can state here with some certainty that the de- 

 terminations of this conchyliologist are wholly inadmissible. 



* From the Bullet de la Soc. Geol. de France, S. 2, vol. ii. p. 41, having 

 been read November 4, 1844. 



t The papers here referred to will be found in Phil, Mag. S. 3. vol. 

 xxiv. p. 222, 224, 308; and vol. xxv. p. 220. 



