568 ARNOLD AND HANNIBAL— MARINE TERTIARY [April 19, 



Excellent plant localities occur at Steel's Crossing near Allen- 

 town, the Fairfax and Montezuma mines on Carbon River, Delazine 

 Creek near Elma, and Skookum Chuck Canon below Bucoda. The 

 Taylor clay mine on Green River, Snoqualmie Pass, the Newcastle 

 mine east of Lake Washington, and a point in the hills south of 

 where the Centralia-Oakville fault crosses Lincoln Creek are also 

 said to have contributed fossil plants belonging to this horizon. 



The following marine invertebrate fauna has been obtained 

 from the Chehalis formation. 



The Olequa Formation. 



Overlying the Chehalis beds is a horizon of the Tejon Series 

 which on Olequa Creek in southern Lewis and northern Cowlitz 

 counties, Washington, contains an excellent flora, and also marine 

 and freshwater faunas. The type section extends from the Erwing 

 ranch a little over two miles above Little Falls southward down 

 Olequa Creek to Olequa, a distance of about five and one-half miles. 

 The beds immediately below Erwing's represent a low east-west 

 syncline in which marine beds are overlain by freshwater deposits, 

 and these in turn by plant-bearing shales. Down the river a low 

 anticlinal axis crosses Olequa Creek a little above Little Falls in the 

 heart of which other freshwater and marine beds are exposed. At 

 the railroad bridge below Little Falls the upper marine and fresh- 

 water beds reappear dipping southward and some distance above 

 them in nearly horizontal strata appears a thin zone of coarse basalt 

 tuff containing numerous marine fossils near the old railroad bridge 

 above Olequa. From here southward the Eocene is mantled by 

 Pliocene basalts associated with river gravels. 



The same horizon of the Eocene reappears, however, at Castle 

 Rock and farther west on Coal Creek above Stella in a more or 

 less regular repetition of low folds with east-west axes. Prob- 

 ably the total thickness of beds in this district does not represent 

 more than 2,000 or 3,000 feet. 



The flora is noteworthy for the abundance of a large palm, prob- 

 ably Calamopsis cf. danae Lx. and of Magnolia cf. Calif ornica Lx. 

 As both these species and one or two others identical with Olequa 



