Diller and Schuchert — Devonian Rocks in California. 41 7 



older than the Carboniferous limestone* and " possibly pre- 

 Carboniferous."f 



Since then Silurian rocks have been discovered in that 

 region.;}: Important contributions concerning the identification 

 and distribution of the Carboniferous, Triassic and Jurassic 

 rocks of northern California have recently been made by 

 Becker,§ Turner,§ Lindgren,§ Hyatt, || Fairbanks,^ Mills,*- and 

 Smith. ff 



A great advance in the study of the Auriferous slates of the 

 Pacific coast is made by Mr. Schuchert in discovering De- 

 vonian fossils among the collections of the U. S. Geological 

 Survey from northern California. In 1884: the writer found a 

 number of coraliferous limestones three miles southwest of 

 Gazelle in Siskiyou County and on the eastern branches of 

 Soda Creek about five miles N.E. of Lower Soda Springs 

 (Castle Crag) in Shasta Co. Mr. H. W. Fairbanks^ in 1891 dis- 

 covered a limestone rich in corals about three miles N.W. of 

 Kennet on the divide between Backbone and Little Backbone 

 Creeks in Shasta Co. Before Mr. Fairbanks' results were pub- 

 lished he kindly called the writer's attention to this locality. 

 In October, 1893, accompanied by Mr. T. W. Stanton the 

 writer made collections there and since then other exposures 

 of the same coraliferous limestone have been found and col- 

 lections made on Hazel Creek a few miles east of Southern's. 



All fossils collected in 1884 and 1893, at the localities men- 

 tioned, were referred to Mr. Schuchert who has definitely 

 determined them to be Devonian as stated in his portion of 

 this communication. 



The outcrop of Devonian rocks three miles southwest of 

 Gazelle is one of the best and most accessible for study yet 

 known in California. They are brought to the surface by an 

 eroded arch which exposes the following series in descending 

 order : quartz and other schists ; 70 feet of fossiliferous gray 

 limestone succeeded by a few feet of compact limestone and a 

 thick mass of basic eruptives. 



West of the axis of the fold this series of Devonian rock 

 dips westward and appears to pass beneath the Scott Mountains. 

 This view is strengthened by the fact that near Parker's on 



* U. S. Geological Survey Bulletin, No. 83, p. 18. 



•f TJ. S. Geological Survey, 8th Annual Report, p. 407. 



JBull. Geol. Soc. of Am., vol. iii, p. 376. 



§ U. S. Geol. Survey, Sacramento and Placerville Atlas sheets, also American 

 Geologist. May, 18.93, pp. 307-324 and 425 and ^pril, 1894, pp. 248-249. 



|| Bull. Geol. Soc. of Am., vol. iii, pp. 395-412 and vol. v, pp. 395-434 



•[[American Geologist, March, 1892, p. 153, February, 1893, p. 69; this 

 Journal, vol. xlv, p. 473, June, 1893; Eleventh Report of the State Mineralogist 

 of Cal., 1893, pp. 24-120. 



**Bull. Geol. Soc. of Am., vol. iii, pp. 413-444. 



ft Bull. Geol. Soc. of Am., vol. v, pp. 243. 



^Eleventh Report of State Mineralogist of Cal. (1S93), p. 48. 



