154 BRUCE CLARK 
simplex zone. With this correlation I do not agree. As stated — 
in the discussion on p. ooo, the species Rimella simplex has not 
been found in the vicinity of Mount Diablo. The specimens 
from the south side of Mount Diablo, determined as such by 
Dickerson, belong to a new species which appears to be character- 
istic of the Meganos horizon. The so-called Rimella simplex beds 
of Mount Diablo come within the Meganos part of the section, 
and contain the typical species of that horizon. 
EOCENE OF THE CAMULOS QUADRANGLE,’ VENTURA COUNTY 
General.—The fourth Eocene section studied during the summer 
of 1918 is that of the Camulos Quadrangle of Ventura County, 
California. The Eocene outcrops are found on both sides of the 
Simi Valley, the best and most complete section being in the 
hills on the south side of the valley, the strike of the beds almost 
paralleling the valley in an east-and-west direction. The late 
W. A. Waring described and mapped the geology of this area. 
He recognized two Eocene divisions in this section, the Martinez 
and the Tejon, stating that apparently the Martinez (Lower 
Eocene) graded up into the Tejon. The fauna figured and 
described by him in his paper as Tejon is that of the Meganos. 
However, the Tejon also is represented in this section resting 
unconformably upon the Meganos. 
Lithology—This general area is being mapped and described 
by Dr. William S. W. Kew of the United States Geological Survey. 
According to him, the maximum thickness of the beds here referred 
to the Meganos is about three thousand five hundred feet. They 
consist principally of bluish-gray shales and shaly sandstones. 
Massive conglomerates are found near but not at the base. No 
sharp line of division between the Martinez and the Meganos 
has been found in this section. This, very. possibly, is due to the 
lack of sufficient detailed work. The Tejon here consists of a 
series of about one thousand five hundred feet of coarse sand- 
«The eastern half of Camulos Quadrangle comprises the Santa Susana and 
Calabasas quadrangles. 
2W. A. Waring, ‘Stratigraphic and Faunal Relations of the Martinez to the 
Chico and Tejon of Southern California,” Proc. Cal. Acad. Sci., 4th ser., Vols Vil 
(1917), No. 4, pp. 41-124, Pls. 7-16. 
