514 STRATIGRAPHICAL GEOLOGY 



were evidently formed in the same sea, while those of Southern 

 France belonged to a different marine province. Those of the 

 Paris basin may first claim attention, and the following is a brief 

 notice of them (see table on p. 491). 



Albian. The name of this stage is taken from the river Aube 

 (or Alba), and in the department of that name it consists of the 

 following members : 



Feet. 



Marls with Schlcenbachia rostrata and Ostrea vesiculosa . up to 200 

 Clays with Hoplites splendens and H. auritus - . . . , 30 



Clays with Hoplites interruptus and Douvilleicf.rns mammillatum ,, 60 

 Green sands without fossils ., 30 



Traced northward into the Departments of the Meuse and 

 Ardenne the basal sands contain D. mammillatum, and pass into a 

 siliceous rock (the " gaize de Draize "). The marls also pass into 

 similar rock (the "gaize de 1'Argonne "), which closely resembles 

 our malmstone, and is undoubtedly of the same age. Still farther 

 north, near Mons, the zone of Sch. rostrata overlaps the lower beds, 

 and is represented by sands with layers and nodules of chert, the 

 fauna resembling that of the Blackdown sands in Devon. 



These Albian deposits pass completely under the Paris basin. 

 They have been readied by deep borings at Paris and Dieppe. 

 They appear again in the anticlinal uplift of the Pays de Bray, and 

 in diminished thickness they are found in the cliffs of Normandy. 

 Near Gap la Heve the clays are about 10 feet, and the gaize with 

 Schlcenbachia rostrata is about 26 feet thick. 



Cenomanian. The district where this stage was first estab- 

 lished, that of Le Mans in the Sarthe, is unfortunately one where 

 the beds have a sandy and shallow-water facies, and are difficult 

 to compare with the chalky facies which prevails in the eastern 

 part of the Paris basin as it does in England. In Normandy, 

 however, there is an intermediate type which affords valuable 

 assistance in the correlation, and a fine section of it is visible in 



the cliffs near Cap la Heve: - 8 



Feet. 



4. Greyish-white chalk with grey flints .... about 30 

 3. Grey chalk with cherts and phosphatic nodules . . ,,10 



2. Yellowish-grey silty andglauconitic chalk with many layers 

 of grey and black cherts, and some beds of bluish marly 



chalk near the bottom . ,,84 



1. Bluish-grey sandy glauconitic marl with black phosphatic 



nodules and many fossils ...... ,,6 



The basement bed contains Stauronema Carteri and Schlcenbachia 

 varians, and is the equivalent of oiir Chloritic marl. The beds 

 above contain Schlcenbachia varians, Acanthoceras Mantelli, 



