AMMONITES — ZOOLOGICAL, ETC. 



339 



than the Paris basin, and a fauna infinitely more abun- 

 dant in pelagic animals, such as the Ammonites must have 

 been. 



I have also made another general observation, which is, 

 that the strata of the Neocomien appear to have been depo- 

 sited tranquilly, as I have nowhere observed great alterations, 

 such as I have remarked in the Gault. 



The species of Ammonites found distributed in all the 

 basins, are: 1st. in the lower strata A. asterianus, cryp- 

 toceras, Leopoldinus, difficilis, radiatusy 2nd. in the upper 

 strata, A. Nisus. 



2nd Group. — Gault or lower Greensand. 



This Group is much more extended over France than the 

 Neocomien. We find it in the Proven9al basin at Escra- 

 gnolle (Var), and at Saint-Paul-Trois-Chateaux. In the Paris 

 basin at Wissant (Pas-de-Calais), at H^vre (Seine Infe- 

 rieure), at Beauvais (Oise), and in the Departments of 

 Aube, Yonne and Haute-Marne. In the basin of the south- 

 west, it is noticed, in the Department of Aube. In the Jura, 

 Savoy, and the Department of Ain, it is also widely extend- 

 ed, as well as in the Ardennes. The following are the sepa- 

 rate faunas of these different basins or localities. 



A, fissicostatus, 



A, Mpims, 

 BeaudantL 

 Camatteanus. 

 DelarueL 

 interruptus. 



PROVENCAL BASIN. 



Lower Beds. 

 A, Milletianus, A, 



Upper Beds, 



A, Lyelli. 



latidorsatus, 

 mammillaris, 

 Majoriams. 

 ParandierL 



A, Roissyanus, 

 Senequierianus. 

 vei'sicostatus^. 



