10 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4TH SER. 
From the Straits of Carquinez they extend easterly, forming 
a well defined belt along the northern border of Mount Diablo, 
which can be followed as far eastward as Byron or Brentwood. 
Farther south the more important areas that have been noted 
are at Corral Hollow,’ New Idria, Coalinga,’ and southward. 
While Eocene rocks have not been followed continuously 
along the range, it is perhaps due to lack of exploration rather 
than to their absence. From New Idria the Eocene can be 
followed westerly for an indefinite distance, while to the east 
and south it has been followed continuously to Coalinga. The 
following list of fossils was obtained by the writer at Corral 
Hollow, from a stratum a few hundred feet above the Eureka 
vein of the Tesla coal mine: 
Neverita secta GABB Tellina longa GasB 
Tritonium sp. undet. Leda gabbi ConrapD 
Turritella uvasana GABB Solen stantoni WEAVER 
Dentalium cooperi GaBB Lucina (?) cretacea GABB 
Amauropsis alveata GABB Mactra sp. undescr. 
Act@on sp. undescr. Meretrix horni Gasp 
On the south side of the canyon other Eocene species were 
obtained, and it is evident that most of the coal veins of this 
vicinity are in rocks of Eocene age. 
H. W. Turner’ recognized the white sandstones occurring 
at New Idria as of Eocene age and reports the following 
species from De Los Reyes canyon: 
Ostrea idriaénsis GABB Morio (Sconsia) tuberculatus GABB 
Neverita globosa GABB Amauropsis alveata GABB 
Rimella canalifera GaBp Meretrix uvasana CoNRAD 
Cylichna costata GABB Turritella, fragment 
Within 50 feet of the coal vein occurring near by he ob- 
tained : 
Solen (Hypogella) diegoén- Neverita sp. undet. 
sis GABB Small lamellibranchs 
1 Geol. Surv. Calif. Geol. v. 1, pp. 34 et seq. 
2U. S. Geol. Surv. Monog. no. 13, pp. 291-309. 
3 Proc. Calif. Acad. Sci. 3d ser. Geol. v. 2, no. 2, pp. 162 et seq. 
4 Am. Geol. v. 14, pp. 92-96. 
