566 WARREN S. SMITH 



Correlation. — Knowlton has done the paleontologic work on the 

 continental Eocene of Washington. He has made the determina- 

 tions both for the Eocene (Puget) of western Washington and for 

 the Eocene (Swauk, Teanaway, and Roslyn) of eastern Washington. 

 Continual reference is therefore made to him as an authority. 

 The original report on the Swauk 1 showed 25 species belonging 

 to the following genera: Lygodium, Sabal, Myrica, Comptonia, 

 Populus, Quercus, Ficus, Cinnamomum, Primus, Diospyros, Zizy- 

 phus, Celastrinites, Phyllites. Of these genera, Sabal, Populus, 

 and Ficus are reported by Miss Duror from the Skykomish Basin, 

 and both Sabal and Ficus are index fossils of the lower Eocene 

 (Puget), as stated by Knowlton: "The following genera have been 

 found in the lower beds but not at all in the upper: Cladophlebis, 

 Lastrea, Siphonites, Ficus, Eucalyptus, and Aralia." 2 Turning to 

 the western area we find that the Puget formation consists of some 

 10,000 feet of arkoses and intercalated carboniferous shales repre- 

 senting the Eocene. Besides the above named, Knowlton describes 

 Quercus, Juglans, Rhamus, Populus, and Laurus from that series. 

 Of these Miss Duror reports Juglans, Populus, and Laurus, and 

 the presence of Ficus and Sabal correlates the Swauk with the 

 lower Puget (Carbonado). Miss Duror's report further proves 

 the equivalency in age of the Swauk with the Fort Union of Mon- 

 tana, North Dakota, and Wyoming. 3 The Swauk sedimentary 

 series may then be correlated with the lower Puget of western 

 Washington, with the Swauk (lowermost Eocene) of eastern Wash- 

 inton, and with the Fort Union areas farther east. 



MIOCENE 



Keechelus. — This series of rocks of volcanic origin comprises 

 tuffs, sheets, and dikes usually of andesitic but less frequently of 

 dacitic composition. The tuffs predominate strongly and form 

 beds of unknown but considerable thickness widely distributed in 

 the Skykomish Basin. They overlie the Swauk sandstone, and the 



1 Folio 106, U.S.G.S., 1904, p. 5. 



2 Folio 54, U.S.G.S., 1899, p. 3. 



3 A. G. Leonard, "Cretaceous and Tertiary Formations," Jour. Geo!., XIX (191 1), 

 541-43- 



