1914] Dickerson: Fauna of the Martinez Eocene of Calif ornia 67 



the Tejon. On the average it is composed of about two thousand feet of 

 thick-bedded sandstones and conglomerates. Its geographical extent as at 

 present known is confined to southern Lake County and a belt extending north 

 and south across Carquinez Strait. Its position in the geological scale seems 

 to correspond most closely to a portion or all of the lower quarter of the 

 Eocene. 



Arnold 7 gave a list of fossils compiled from the papers of Stanton, 

 Merriam, and Weaver, added a few new species obtained "from a 

 locality of doubtful Martinez age," and described Pecten proavus 

 from this locality in Santa Cruz County. He mentioned Rock Creek, 

 Los Angeles County as a Martinez locality. In a later paper 8 he 

 described the Santa Cruz locality, gave a list of fossils obtained from 

 it and described Cidaris merriami, Semele gayi, Tritonium newsomi, 

 Hipponyx carpenteri, Patella mateoensis, and Fissurella perrini. He 

 described the Martinez ( ?) of the Santa Cruz Quadrangle as follows: 



The diabase dike exposed north of the headwaters of Pescadero Creek has 

 brought up considerable inclusions of impure limestone which, from the fossils 

 found in them, appear to be of Eocene age. Obviously the stratigraphic rela- 

 tions of this great limestone inclusion are unknown, but the fossils indicate 

 its Eocene age and that it probably belongs in the lower part of the formation. 

 The following fauna occurs in this limestone: 



List of Lower Eocene Fossils from the Santa Cruz Quadrangle 



echinoidea 



Cidaris merriami, new species 

 Brachiopoda 



Terebratalia, new species, m. T erebratulina tejonensis Stanton 



Terebratalia, new species, p. 



Pelecypoda 



Pecten proavus Arnold Semele gayi Arnold 



Gastropoda 



Chlorostoma, new species, c. Patella, new species, b. 



Cylindrites brevis(?) Gabb Patella mateoensis Arnold 



Fissurella perrini Arnold Thylacodes, new species, w. 



Hipponyx carpenteri Arnold Tritonium newsomi Arnold 



Odostomia, new species, b. 



i Arnold, Ralph, The Tertiary and Quaternary Pectens of California, Profes- 

 sional Paper no. 47, IT. S. Geological Survey, pp. 11-12, 1906. 



s Arnold, Ralph, Descriptions of New Cretaceous and Tertiary Fossils from 

 the Santa Cruz Mountains, California, Proceedings of the United States National 

 Museum, vol. 34, no. 1617, pp. 347, 359-363, August, 1908. 



