102 



THE LIAS AMMONITES. 



and Lyt. Uneatum, and in the upper zone Amal. margaritatus is associated with Amal. 

 spinatus. It would appear that Amal. magaritatus has a considerable vertical range, 

 both in Germany and Prance, and thereby links together the Henleyi and Spinatus 

 horizons in these countries by a persistent Cephalopodous type. Amaltheus margaritatus 

 is thus remarkable alike for its zoological characters, and its wide distribution in time 

 and space. 



In Prance the Margaritatus-heAs, are exposed at Vieux-Pont, Calvados. Professor 

 Deslongchamps^ has given a section of this, which evidently represents the English 

 Marlstone ; it consists of a Rock-bed about five feet in thickness, enclosing a large 

 assemblage of fossils, of which the most characteristic are Amal. margaritatus, Amal. 

 spinatus, Belemnites niger, Peden cequivalvis, Pecten disciformis, Lima jmndata, 

 Terehratula quadrifda, Ter. cornuta, Ter. ptmdata, Ter. Edwardsii, PJignchonella acuta, 

 Pliyn. tetraedra, Bpiriferina rostrata. Its upper portion is characterised by a particular 

 stratum charged with small Gastropods of the genera Turho, Cerithium, Tornatella, 

 Adceonhia, and sometimes Pleurotomaria i^recatoria. In the adjoining region, as at 

 Evrecy, Landes, Cnrcy, and Croisilles, the same bed is found maintaining its lithological 

 and palseontological characters with a remarkable constancy. This zone has an extensive 

 distribution in other Departments of France, and the characteristic Ammonites are found 

 near Nancy, Meurthe ; Saint-Rambert, Ain ; Venarey, near Semur, and Pouilly in 

 Auxois Cote d'Or ; St. Amand, Cher ; Metz, Moselle ; Avallon, Yonne ; near Lyons, 

 Rhone; Clapier and Bosc, Aveyron; where it is associated with a number of new 

 Ammonite forms that appear to be special to the Mediterranean area. 



The late Dr. Reynes, of Marseilles, collected, figured, and described these Cephalopods, 

 which were chiefiy obtained from the Margaritatus\s^$i^ at Clapier, Bosc, Riviere, 

 Tournemire ; and has given the following remarkable list^ from this portion of the Depart- 

 ment of the Aveyron : 



Cephalopoda. 



Belemnites el oiigatus, Mill. 



— niger. Mill. 



— breviformis, Voltz. 

 Nautilus, sp. 



Ammonites spinatus, Brug. 



— margaritatus, Montf. 



— mimatensis, d'Orh. 



— Mgion, d'Orh. 



— Eagazzonii, Hauer. 



— acanthoides, Reynes. 



— pseudoradians, Ret/. 



— Nilssoni, Hubert. 



Ammonites Algovianus, Oppel. 



— Alberti, Rey. 



— Herbeti, Rey. 



— ruthenensis, Rey. 



— Partschi, Slur. 



— Boscensis, Rey. 



— Loscombi, Sow. 



— Kurrianus, Oppel. 



— instabilis, Rey. 



— Fieldingi, Rey. 



— plainspira, Rey. 



— disciformis, Rey. 



1 ' Etudes sur les Stages Jurass. infer, de la Normandie,' p. 51, 1864. 

 - ' Geologic et de Paleontologie Aveyronnaises,' p. 50, 1S68. 



