Ixx 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



The following table will give some idea of the geological series of 

 the Corbiere formations as established by M. d'Archiac : — 



System. Formation. Group. Etage. 



Recent. 



Quaternary. 

 Tertiary .... 



Middle ? 



Lower 



Molasse. 

 ' Nummulitic 



ofAlet. 



' Upper 1. 2. 



f Cretaceous < 



1. 

 2. 

 3. 

 1. 

 2. 

 3. 

 1. 

 2. 

 3. 

 4. 



Secondary 



^ Lower « 



3. Wanting, 

 r 1. Wanting. 



4. Neocomian< 2. 



u. 



V. Jurassic Lias Upper. 



Transition I Carboniferous (Coal). 



(Interm^diaire.) \ Devonian? 



Primary Granite. 



Igneous rocks (diorites, amygdaloids and spilites, basalts, wackes, &c.). 

 Metamorphic or uncertain (dolomite, cargnieule, gypsum, salt ?). 



The present paper only embraces the Cretaceous formation ; 

 M. d'Archiac reserves for a future opportunity the Jurassic and 

 underlying formations. 



M. Constant Prevost has announced to the Academic des Sciences* 

 the interesting discovery in the conglomerate-bed, between the piso- 

 litic limestone and the plastic clay, near Meudon, of the tibia of a 

 fossil bird of gigantic size. This conglomerate had, according to 

 M. Elie de Beaumont, already produced numerous bones and teeth 

 of Mammifers and Reptiles. But this discovery of a Bird was pro- 

 nounced by M. Valenciennes to be one of the most interesting osteo- 

 logical discoveries made in the Paris basin since the days of Cuvier. 

 The bird belonged to the family of Natatores, and must have been 

 nearly two or three times the size of a swan. It has been called 

 Gastornis parisiensis, Heb. M. Hubert subsequently announced the 

 discovery of a femur of the Gastornis parisiensis, found in the same 

 bed as that containing the tibia, and within 10 feet of it. 



With reference to the paper by MM. Hebert and Renevier on the 

 Nummulitic formations in Switzerland alluded to in my address last 

 year, I may mention that M. Renevier has since published in the "Bul- 

 letin de la Societe Vaudoise des Sciences Naturelles," a more correct 

 and detailed account of his subsequent investigations of this forma- 

 tion, although he considers that the term Nummulitic is no longer 

 appropriately applicable to the Tertiary strata of the Vaudoise Alps. 

 M. Renevier had originally divided this formation into two beds, 

 viz. the Cerithium and the Nummulitic, of which the Cerithium 

 bed was the more recent. Subsequently, however, he received infor- 



* Comptfis Rendus, tome xl. 



