2 CALIFORNIA ACADEMY OF SCIENCES [Peoc. 4th Ser. 



along the Strait of Juan de Fuca, the low hills about Tenino 

 and Centralia in Chehalis County and the exposures on Coal 

 Creek north of Columbia River in Cowlitz County. At these 

 localities only fragmentary sections of the Eocene column of 

 Washington can be studied. The region under discussion in 

 this paper contains the most complete fossiliferous marine sec- 

 tion occurring within the western portion of the state. 



REVIEW OF LITERATURE 



One of the earliest important scientific references to the 

 geologic conditions in this region is to be found in the report 

 by Dr. Ralph Arnold^ on "The Tertiary and Quaternary Pec- 

 tens of California." He described Pecten landesi from this 

 area. The following quotation is well worth noting: '^P. 

 landesi is found quite abundantly in a dark greenish sandstone 

 bed that outcrops about 100 yards west of the junction of Still- 

 water and Olequah creeks (U. S. Nat. Mus. locality 4019) one- 

 fourth mile southwest of Little Falls, Lewis County, Wash. It 

 is also found in a similar matrix in the bed of Olequah Creek 

 (U. S. Nat. Mus. locality 4024), one mile north of the first 

 locality. It is associated in this formation with a characteristic 

 Eocene fauna, among which are the following species : Veneri- 

 cardia planicosta Lamarck, Thracia dillcri Dall, Crassatellites 

 sp., Meretrix sp., Ostrea sp., Pteria (cf.) limula Conrad, Car- 

 dium 2 sp., Barbatia sp., Glycimeris sp., Corhnla sp., Callista 

 sp., Turritclla (cf.) uvasana Conrad, Fusus 4 sp., Ocinebra 

 sp., Ranella sp., Calyptrophonis sp., Lunatia sp., Turbinella 

 (?) sp., Murex 2 sp.. Conns sp.. Cassis sp., Tritonium sp., 

 DcntaUmn (cf.) cooperi Gabb, and Nautilus sp. This horizon 

 is probably upper Eocene, possibly above the Tejon." Dr. Ar- 

 nold's suggestion that this horizon is very high in the Eocene 

 seems to be well in accord with more recent studies. 



The Geology and Paleontology of this area is discussed in 

 a paper by the writer=^ published in 1912. A large fauna was 

 noted as occurring along the banks of Cowlitz River about one 



'Arnold. Ralph, The Tertiary and Quaternary Pectens of California. Professional 

 Paper 47, U. S. Geol. Surv., p. 52, 1906. 



'Weaver, C. E., "A Preliminary Report on the Tertiary Palaeontology of Western 

 Washington," Bull. 15, Wash. Geol. Surv., pp. 12-15, 1912. 



