University of California Publications in Geology [Vol. 8 



Other Localities 



Other localities in Contra Costa county from which fossils of San 

 Pablo age listed in this paper were obtained are Las Trampas Ridge, 

 Lafayette Ridge, and southwest of Danville. 



Las Trampas Ridge. — Las Trampas Ridge lies less than a mile east 

 of and parallel to Rocky Ridge. The San Pablo outcrops on the south 

 side of the ridge and dips to the southwest at an angle of 60° to 70° ; 

 it rests upon the Monterey with relations analagous to those observed 

 on Rocky Ridge. The two major faunal zones of the San Pablo are 

 recognized here. Scutella gabbii is found at the base of the group, and 

 Astrodapsis tumidus, subsp. cierboensis and other characteristic lower 

 San Pablo species occur at a slightly higher level. A very good upper 

 San Pablo fauna was obtained near the top of the group at locality 

 1182. 



Lafayette Ridge. — A few localities including Nos. 145, 149, 1195, 

 and 1197, are listed from Lafayette Ridge, which is practically a con- 

 tinuation of the section on the north side of the Tice Valley syncline ; 

 the two major faunal zones are recognized here. 



Danville. — San Pablo outcrops occur on the north side of Las 

 Trampas Ridge a short distance southwest of Danville, but the section 

 is obscure. C. E. Weaver listed several species from one locality which 

 the writer has also visited. A typical San Pablo fauna, including two 

 new species of gasteropods, Tegula (Chlorostoma) trampasensis and 

 Leptotliyra danvillensis, was obtained here and is listed under localities 

 1635 and 1636. 



COMPLETE LIST OF KNOWN- SPECIES PROM THE SAN 

 PABLO GROUP OP MIDDLE CALIFORNIA, WITH 

 THEIR GEOLOGIC RANGE 



The following is a complete list of the species from the different 

 sections described in this paper. The different zones in which the 

 species occur are indicated in the columns. With the exception of 

 the collections belonging to the University of California, the chief 

 sources of information in regard to the species common to the San 

 Pablo, Santa Margarita, Jacalitos and Etchegoin, have been Dr. J. P. 

 Smith's 23 paper on the "Geologic Range of Miocene Invertebrate 

 Fossils of California" and the collections of the California Academy 

 of Sciences in San Francisco. 



23 Proc. Calif. Acad. Sei., 4th series, vol. 3, pp. 161-182. 



