OP THE SWISS JURA AND ENGLAND. 



231 



north-east part of the district these beds immediately overlie the 

 Calcaire rouse sableusc, and in the south-west region the Dalle ?iacree, 

 both of which are included in the Bathonian. They are overlain in 

 the southern chains by the Calcaire a Scy-phies inferieur, and in the 

 northern chains by the Couche marneuse a Cidaris lazviuscula, i. e. 

 Oxfordian. M. Mathey considers that the Dalle nacree overlies the 

 Zone a Ammonites macrocephalus. (" Coupes Geologiques des Tunnels 

 du Doubs," extr. from Denkschriften d. Schweiz. Gesellsch. f. d. ges. 

 JS"aturw. Band xxix. pp. 7 and 15.) ChofFat supports the same view 

 (Esquisse du Callovien et de l'Oxfordien, pp. 19, 20). He would 

 also exclude the Callovian from the Jura superieur (Jornal de 

 Sciencias Mathematicas, &c. no. xl., 1885), an opinion which is con- 

 troverted by Neumayr (Neues Jahrb. f. Mineral. Geol. &c, 1884, 

 pp. 227-230). The most generally accepted view, however, appears 

 to be that which is adopted by Greppin. 



The Zone of A. macrocephalus, both by its fauna and penological 

 characters, is easily recognized. It is described as a rough, red, 

 grey, or blackish limestone, alternating with clays of the same 

 colour, and having a thickness of from 3 to 6 feet. 



The exposures in it are not numerous, since it usually forms low 

 ground. A small section was seen on the roadside above Mont- 

 melon, showing the following beds : — 



1. Oolithe corallien. 



2. Terrain a chailles. 



3. Oxfordien. 



4. (Nothing seen ; probably occupied by the clayey portion of the Callovien.) 



5. Callovien, a coarse oolitic ferruginous limestone with fossils. 



The beds immediately overlying and underlying the Callovian 

 were not shown. 



A rock possessing the same lithological characters as the above- 

 mentioned Callovian was pointed out to us by M. Mathey, amongst 

 the material obtained from the Glovelier tunnel, where these beds 

 were cut through. 



The following fossils were obtained by us from these two loca- 

 lities : — 



Callovian Fossils. 





Montmelon. 



Glovelier 







Tunnel. 



Belemnites hastatus, Blainv 







Ammonites hecticus, Eein 





# 



anceps, Eein 









* 









* 





* 





Gowerianus, Sow. ? 



* 





Turbo bijugatus, Querist 



* 





Terebratula dorsoplicata, Suess 



* 



* 



Rhynchonella, sp 





* 



