FAUNAL RELATIONSHIPS OF THE MEGANOS GROUP 161 
southeast of Mount Diablo. This correlation apparently was 
based primarily on the corals. Dickerson believed that the beds 
of his Turbinolia zone represented a horizon lower than that of 
the type section of the Tejon. Thus, as regards the stratigraphic 
position of his Turbinolia zone with the true Tejon, he and the 
writer are in agreement. Besides the corals, there is a considerable 
number of highly ornamental molluscan species common to the 
Meganos of the Mount Diablo and Coalinga regions. A very 
large proportion of these are new species belonging to such genera 
as Meretrix, Rimella, Turris, Ficopsis, Galeodea, Turritella, etc. 
One of the described gastropod species, found in all three of the 
Meganos sections under discussion, is Turritella andersoni. This 
species appears to be a marker of the Meganos horizon. 
The evidence for the correlation of the Meganos of the Coalinga 
region with that of the Camulos Quadrangle in Ventura County 
is even more conclusive. The faunas of the Meganos of these 
two localities have a very large proportion of their species in 
common, while in the more southern locality, Camulos Quadrangle, 
a number of species are found which are common to the Meganos 
of the Mount Diablo region, but which have not been found in 
the Coalinga region; among these are Ancilla (Oliverata) cali- 
fornica Cooper, Galeodea sutterensis Dickerson, and Turritella 
merriami Dickerson, none of which, as far as the writer is aware, 
have been found in the beds of typical Tejon. 
CORRELATION OF THE MEGANOS WITH THE SIPHONALIA SUTTERENSIS ZONE 
OF THE IONE FORMATION 
As already stated, it is my conclusion that the Meganos Group, 
originally described from the vicinity of Mount Diablo, belongs 
to the same general epoch of deposition as the beds of the Sipho- 
nalia sutterensis zone described by Dickerson* and which he 
considered the uppermost Eocene of the West Coast, and a part 
of the Ione formation described by Turner from the Jackson 
Quadrangle. 
tR. E. Dickerson, “Note on the Faunal Zones of the Tejon Group,” Univ. Cal. 
Pub. Bull. Dept. Geol., Vol. VIII (1914), No. 2, pp. 17-25; “Stratigraphy and Fauna 
of the Tejon Eocene of California,” Univ. Cal. Pub. Bull. Dept. Geol., Vol. IX (1916), 
No. 17, pp. 363-524, Pls. 36-46. ; 
