4 Bulletin 15 314 



Freshwater limesto7ie and clays; Relation of tlie Rennes 

 fauna to that of Bordeaux; Oligocene in southwest- 

 ern France 32 



Oligocene of the Gironde valley; Section of the Gironde 



Oligocen e 33 



Sa7idstone of Fronsac; Limestone of Castillon and Civrac 34 



The Ostre.i clays; Asterias or Bo7irg limestone 35 



Friable limestone of Agen; Affinities of the Gironde 



To7igrian fau7ia; Aqiiitanian 36 



White limestone of Agen; The sa^idstone of Bazas; 



The grey limestone of Agen 37 



The Shell marl of Lariey; Limestone of Le Son; Oli- 

 gocene of the Adour valley; Correlation of the Adour 

 7narls 38 



Nummulites in the Blue marls; Affinities of the Adour 

 fauna; Oligocene of the Ceritral Plateau 39 



Fontanne' s seHion; Oligocene of the Sa6?ie and Rhone 



valleys; SeHion of the Oligocene of the Mainn basin 40 



PART II. 



ThE' Oligocene of the Southern United States... 42-81 

 General Extent: The Vicksburg limestone; Chattahoo- 

 chee limestojies and clays 42 



Grand Gulf sayidston es; Frio clays 43 



Conditions of Deposition: Physical Geography during 

 the Vicksburg period; Defleflion of the equatorial 



current 43 



Depositions in the Chattahoochee a7id Misssissippi cni- 

 bayments; Tropical fauna of Chipolan ivaters; In- 

 trusion of cold current. Inti'odu£lion of Chesapeake 



species : 44 



The Oligocene Series in Detail in the Several States... 45-81 

 Florida: 



Vicksburg group. Vicksburg U^nestone 45 



Ocala nummu-litic li^nestone * 46 



Chattahoochee Group. Langdori' s discovery of the 



Chattahoochee beds 47 



The Chattahoochee series in central Florida; The 



Orthaulax bed 48 



