142 BRUCE CLARK 
Correlation.—Later work has shown that the faunas of the 
Turbinolia zone and the Rimella simplex zone belong to the 
Meganos epoch, while the fauna of the Balanophyllia zone repre- 
sents typical Tejon.’ A fairly large number of what are believed 
to be distinctive markers of the Meganos have been found in 
the beds referred to the lower two zones just mentioned. A few 
’ of the more important of these species which have been found in 
other Meganos localities and may be considered as markers of 
that horizon are: Schizaster diabloensis Kew, Turbinolia pusillanima 
Nomland, Venericardia cf. merriami Dickerson, Trochocyathus 
imperialis Nomland, Ancilla (Oliverata) California Cooper, Rimella, 
n. sp., Siphonalia sutterensis Dickerson, Turritella merriami Dick- 
erson, Turritella andersoni Dickerson. In the beds representing 
the other zone, equally good evidence was obtained for corre- 
lating them with the typical Tejon. 
It is interesting to note at this point that at the time Dickerson 
wrote his paper ‘‘Stratigraphy and Fauna of the Tejon Eocene 
of California,’ Arnold, Hannibal, and W. A. Waring correlated 
the Tejon in the vicinity of Mount Diablo with the Ione as 
recognized by them, which they recognized as an epoch distinct 
from and later than the Tejon. The faunas collected by Arnold 
and Hannibal, and by Waring from the Mount Diablo region 
appear to have come from the basal beds of the Eocene to the 
south and southeast of the mountain, Dickerson’s lower Tejon 
recognized by the writer as Meganos. The locality from which the 
original so-called Ione marine fauna was obtained by these writers, 
with which they correlated the Mount Diablo fauna, was the 
south side of Table Mountain. ‘This may be considered the type 
of Dickerson’s Siphonalia sutterensis zone, the fauna of which he 
thought represented the highest horizon of the West Coast Eocene. 
This horizon is here placed well down in the Eocene, below the 
Tejon. Thus Arnold and Hannibal and Waring agree with the 
writer in their correlation of these lower beds in the Eocene section 
on the south side of Mount Diablo with the Eocene of Oroville, 
but they erred in regarding their Ione the uppermost Eocene of the 
Pacific Coast. ‘They erred with Dickerson in their interpretation 
«The species listed by Dickerson as Rimella simplex is a new species. 
