144 BRUCE CLARK 
to the Meganos Group, were of Tejon age. My conclusion was 
stated as follows:* 
After studying the fauna from the Turritella andersoni beds, the same 
material on which Dickerson based.his conclusions, the writer was impressed 
with the fact that there are so few typical Tejon species in this fauna. He does 
not agree with a number of the specific determinations that Dickerson made, 
as given in his list from locality 1817. Evidently Dickerson did not consider 
the possibility of there being a third group coming in between the Martinez 
and the Tejon, and that if this were so, one might well expect to find a larger 
number of species bridging the gap between this intermediate horizon and the 
Tejon than the gap between the Martinez and the Tejon. 
Study of the Eocene series to the north of Coalinga showed 
conclusively that there is an unconformity in this section, and 
that the fauna obtained from above this contact is that of the 
typical Tejon, while the fauna below is referable to the Meganos. 
It is not the purpose in this paper to describe the lithology of the 
Eocene of this section except incidentally. Anderson and Pack 
of the United States Geological Survey have already described the 
lithology of this section’ in detail. Accompanying their paper is 
a geologic map of the area. They referred the beds below the 
contact to the Martinez, and those above to the Tejon. The 
writer followed this contact nearly 20 miles, from a point near 
the old station of Oil City, to the Arroyo Honda near the west 
border of the Coalinga Quadrangle. Good evidence of an uncon- 
formable relationship was found along the entire distance. 
As seen between the southern end of Domengine Creek and 
Cantua Creek (Coalinga Quadrangie), the upper beds of the 
Meganos consist of a white sandstone, which was mapped by 
Anderson and Pack as a part of the Tejon. The contact be- 
tween the Meganos and the Tejon comes in between this sand- 
stone and somewhat similar sandstones of the Tejon. It is, as 
a rule, marked by a conglomerate, and is irregular at numerous 
t Bruce L. Clark, ‘“Meganos Group, a Newly Recognized Division of the Eocene 
of California,” Bull. Geol. Soc. Amer., Vol. XXIX (1918), No. 2, p. 294. 
2 Robert Anderson and Robert Pack, “‘Geology and Oil Resources of the West 
Border of the San Joaquin Valley, North of Coalinga, California,” U.S. Geol. Survey, 
Bull. 603 (1915), p. 66. 
3 Anderson and Pack, op. cit., p. 66. 
