1916] Martin: Pliocene of Middle and Northern California 219 



certainly younger than the Empire Beds of Coos Bay and older than 

 the Merced south of San Francisco. In a later note, inserted in 

 the same publication (page 39), Dr. Dall reported, after having 

 visited the region himself, "that the characteristics of the fauna 

 point to an upper Miocene age and no distinctly Pliocene species 

 of mollusks appear in it anywhere." Some of the sands and gravels 

 toward the ocean appeared to be quite recent and it was considered 

 by Dall that these might even be Pleistocene. The deposition of 

 this series was considered continuous from the upper Miocene to some 

 time in the Pliocene without a marked unconformity, "and with a 

 continuous fauna which changed, if at all, chiefly by some species 

 becoming more rare or disappearing entirely." 



Along Mad River, between North Fork and the mouth of Canon 

 Creek, a formation of soft sandstone was exposed which formed 

 the low hills along the east side of the coastal plain. A small num- 

 ber of fossil marine mollusks obtained from these beds were identi- 

 fied by Dr. Dall, who questionably placed the beds in the Pliocene. 



At Battery Point, near Crescent City, California, a section is 

 described at the base of which is a formation of soft bluish sand- 

 stone containing pebbles and a few fossil invertebrates, among them 

 Terebratalia hemphilli Dall, which points toward a Pliocene age. 

 Above this member there are non-fossiliferous yellowish sands and 

 clays with some pebbles at the base. The whole series is uncon- 

 formable above a much altered sandstone of Pre-Tertiary age. 



A similar section is exposed at Pebble Beach, two miles north 

 of Crescent City. Here the bluish sandstone containing Terebratalia 

 hemphilli is apparently lacking, and the soft non-fossiliferous yel- 

 lowish sand is lying horizontally upon Miocene strata which were 

 tilted slightly to the northwest. The Miocene beds were unconform- 

 able upon the much altered Pre-Tertiary sandstone. 



At Point St. George, a few miles north of Crescent City, Diller 

 described a formation of soft yellowish and gray shaly sandstone 

 and whitish shale, less than one hundred feet in thickness, which 

 contained a fauna that warranted its determination as Miocene of 

 the Empire horizon. 



At Cape Blanco, Oregon, about forty miles north of the Califor- 

 nia boundary, Diller described Neocene and Quarternary sedi- 

 ments which are more or less closely related to the later Tertiary 

 formations of California. The Neocene is represented by a series 

 of yellow sandstones, tuff, light-gray sand beds, conglomerate, and 



