Vol. VII] DICKERSON— CLIMATE AND OLIGOCENE FAUNAS 159 



the locality and incidental stratigraphy as follows : "Locality 

 181, on the east bank of the Cowlitz River just back of the 

 Greeco ranch house, about four miles east of Vader, Wash- 

 ington. There appear to be two formations represented at this 

 point. The fossils occur in a sandstone formation which is 

 associated with a conglomerate. The upper zone which is 

 mostly Ostrea is in a conglomerate composed of basalt pebbles 

 and boulders. The lower zone is nearly all small gastropods 

 which occur in blue sandstone. These two beds dip north- 

 west at a very small angle — about 0°-5°. A few yards to the 

 south, a well stratified, coarse, gray, compact sandstone is 

 exposed dipping south at an angle of 10° and striking N. 

 70° E. This sandstone is probably Eocene. About 20 feet 

 south of the fossil beds a mass of coarse conglomerate is but- 

 ting perpendicularly against the sand to the south. This con- 

 glomerate appears to be the same as that where the fossils 

 occur." 



The matrix in which this fauna occurs is much coarser than 

 most of the fossil bearing rocks of the Oligocene, which are, 

 in general, shaly in this region. Perhaps it may be that Mar- 

 tin has described an unconformity between Oligocene strata 

 and the Tejon-Eocene rather than a fault. 



Fauna 



The fauna collected by Messrs. Anderson and Martin is 

 particularly rich in tropical species and the number of species 

 found at one locality — 48— is large. This fauna is listed 

 below. 



List of species from California Academy of Sciences 

 Locality 181 



Astarte perrini, new species. 

 Area washingtoniana, new species. 

 Barbatia gabbi, new species. 

 Cardium lincolnensis Weaver. 

 Cardita weaveri, new species. 

 Chama pacifica, new species. 

 Corbula cowlitzensis, new species. 



