1869.] COQUAND CRETACEOUS STRATA. 239 



MIDDLE CEETACEOUS. 

 1st. Rhotomagian stage {Turrilites costatus, Lamk.), wanting. 



2nd. Gardonian stage, with lignites 6 metres. 



{a) Lower portion, with ;^A(?r./oZ«acgM5 

 and Ostrea hiauriculata ("Bancs a 



Srd rarentonian staxrp J Ostracees" de M. d'Archiac) 67 



° • (o) Upper portion, with Inoc. labiatus 

 and Amm. rusticus (base of the 



chalk marl and lower chalk) 25 



4th. Angoumian stage, with Eadiolites lombricalis (wanting in 



England) 40 



5th. Provencian stage, with Hipjpurites organisans, Desml. (want- 

 ing in England) 37 



175 

 UPPER CRETACEOUS. 



1st. Coniacian stage (Gres de Cognac) (wanting in England) 40 metres. 



2nd. Santonian stage (of Saintes) (superior Lower Chalk = chalk- 

 marl, upper part) 65 „ 



3rd. Campanian stage (Champagne de Cognac = Upper Chalk) 70 ,, 

 4th. Dordonian stage (wanting in England) ... 15 ,, 



190 „ 



These divisions, which are perfectly well marked and of consider- 

 able thickness, and possess peculiar faunas and composition, evidently 

 differ very much from what we may observe in the basin of the 

 Seine and in England, where we pass directly from the chalk marl 

 (Rhotomagian stage) to the Lower Chalk, and thence to the Upper 

 Chalk without the intervention of the Carentonian, Angoumian, 

 Provencian, and Coniacian stages. 



The coast of Provence, however, presents a still more gigantic 

 development of the Cretaceous formation (see fig. 2), and such material 

 difierences from what is met with elsewhere, that in order perfectly 

 to understand the connexion which exists between the system of the 

 south and that of the north of France, an intimate knowledge of the 

 localities is necessary, and the help of fossils is indispensable. And 

 here I may appeal to those English geologists who have had the 

 opportunity of examining our strata. 



Without speaking of the Neocomian strata, the lower green- 

 sand, with Diceras Lonsdalii, the Speeton clay, and the gault, which 

 do not offer any very striking peculiarities, I shall pass at once to 

 the middle and to the upper Cretaceous beds, briefly describing their 

 composition, and their equivalents in England. 



It may perhaps be advisable, on account of its fauna and differ- 

 ence of position, to separate the upper from the lower part of the 

 Carentonian stage, and to form for it another stage, which I shall 

 propose to call the Ligerian. This will have the advantage of giving 

 to the beds with Inoceramus lahiatus an autonomy of their own, and 

 will prevent their being confused, as they must be in the basin of 

 the Loire and in England, with the limestones of the same colour 

 which succeed them without the interposition of the intermediate 

 stages which separate them in Provence, and which contain com- 

 pletely different faunas. 



