147 



The Avictjla contokta, oe Eh^tian, Series. 

 These Arhoses are composed of Sandstone and Marls, with 

 Avicula contorta and the Bone-bed ; the sections given in M. J. 

 Martin's memoir, shewing the presence of these, agree very 

 closely with the order of sequence of the same beds seen in 

 Gloucestershire. 



1. Marcignt-sotjs-Thil. — Lumachelle du lias (assises pen 

 developpees.) 

 LiTHOLOGT. Fauna. 



i Cerethium Semele, d'Orb. Cardium 

 Sandstone, "with, fucoids ... ] cloacinum, Quenst. Avicula Dun- 

 ( keri, T^m. 



Arenaceous strata, formed ) t.t f„„^n-t „ 



.J. i. J A 1 ! Aon-iossmierous. 



of disaggregated Arkose ) 



iPecten Valoniensis, Befr. Avicula 

 contorta, Portl. Mytilus minutus, 

 Gold/. Ostrea marcignyana, Mart, 



("Cliemnitzia Oppeli, Mart. Turbo sub- 

 crenatus, Mart. Anatina prsecursor, 

 Quenst. A. Suessi, Ojq). Myophoria 

 inflata, Emm. M. multiradiata, 

 Emm. Cardium Ehaeticum, Merian. 



"Wliitisli, micaceous, fine- 



grained Sandstone tra-, ^ eloacinum, Quenst. c' Pbilip- 



versed by veins colored 

 by Oxide of Iron 



pianum. Dunk. Avicula contorta, 

 Portl. Lima praecursor, Quenst. 

 Pecten Valoniensis, Defr. With 

 many other new sp. of Gasteropoda 

 and Conchifers. 



Sandstone like the .fove U^^.^^^^jj^f^^^^g^ 

 resting upon Granite j 



2. MoNTiGNT-STjE-ARMANfON. — Lumachelles. Banc de 30 a 35 



centimetres. 



LiTHOLOGT. Fauna. 



Granitoid Arkose ... ... Without any knovrai fossils. 



("Avicula contorta, Portl. Gervillia 



Deep red fine - grained 1 prsecursor, Quenst. Lima praecursor. 



Sandstone, feebly ag-J Quenst. Pinna semistriata, Tqm. 



gregated and browned ] Lima Bochardi, Mart. Ostrea 



by the Oxide of Iron Marcignyna, il/«rf. Anomya irregu- 



i_ laris, Tqm. 



Two sections are given from the S.E. and S.W. of Semur, 

 and another from Pouillenay, which resemble the preceding 

 in their lithological character and organic contents. 



