40 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



Beds about 300 feet above the base (Univ. of Cal. locality 

 458) yielded an excellent fauna. This fauna, however, does 

 not differ essentially from that of the beds higher in the sec- 

 tion. The faunas from several other localities which are listed 

 below do not differ materially from one another but all appear 

 to represent one phase only. This faunal unity is in conso- 

 nance with the sedimentary record as Anderson^^ described it. 

 "The beds throughout possess a marked similarity and give 

 every appearance of representing a period of continuous de- 

 position in one basin. They are therefore to be regarded as 

 making up a formation, and not a larger division of the geo- 

 logic column," 



The writer is in complete agreement with Anderson's views as 

 expressed here in relation to the type Tejon. However, beds 

 both higher and lower than the Eocene of Caiiada de las Uvas 

 occur in other parts of the state, notably in the vicinity of 

 Mount Diablo, along Cantua Creek, Coalinga Quadrangle and 

 at the Marysville Buttes. Owing to these facts the expression 

 — Tejon group — is fully warranted upon both stratigraphic 

 and faunal grounds. 



The fauna of the type Tejon corresponds with zone 2^^ of the 

 Mt. Diablo section. This zone will be called henceforth, the 

 Rimella simplex Zone, after a characteristic fossil in its fauna. 

 It is characterized by the abundance of Turritella uvasana, 

 Rimella simplex, Meretrix ovalis, MacrocalUsta conradiana, 

 Meretrix hornii, and by the absence of the TurhinoUa piissi- 

 lanima, n. sp. and other species of Zone 1 of the Mount Diablo 

 section, and Siphonalia sutler ensis, V enericardia plaiiicosfa 

 merriami and other members of the Siphonalia sutterensis 

 fauna. The greatest extent of the Tejon Sea in California at 

 this stage is represented graphically in the figure on the oppo- 

 site page (see Text Figure 2). The fauna obtained from the 

 type locality of the Tejon group is given below. 



^' Anderson, Robert, Preliminary Report on the Geology and Possible Oil Resources 

 of the South End of the San Joaquin Valley, Cal. Bull. 471, U. S. Geol. Surv., p. 118, 

 1912. 



^ Dickerson, R. E. Note on the Faunal Zones of the Tejon Group, Univ. Calif. 

 Publ. Bull. Dept. Geol., vol. 8, pp. 17-25, 1914. 



