108 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4TH SER. 
are found in the Santa Margarita, none of them are charac- 
teristic of it. 
Since the entire stratigraphic group including Zones a B, 
and C is quite conformable in position, and all its members 
are more closely related to the Temblor in faunal features than 
to any other horizon of the Neocene, it follows that if any 
_ part of the included strata is to be referred to a horizon other 
than the Temblor, it must be done upon the basis of criteria 
other than stratigraphical or paleontological. In the matter 
of thickness also there is little to warrant any subdivision of 
these beds. 
The Temblor beds described in former papers devoted to 
the Mt. Diablo Range have in their type-locality an aggregate 
thickness of 1500 feet. Northward along the range the thick- 
ness diminishes until at Coalinga and on Cantua Creek it is 
hardly more than 300 feet. 
In the San Emidio section it is not easy to say how much of 
the Miocene is to be classed as Temblor, but, judging from 
Whitney’s description, it is not less than 1500 feet and may 
be more. The writer’s estimate has been greater than this. 
In the Kern River area the Lower Miocene beds, including 
Zones A and B, would have only an average thickness; and 
including all of the fossil-bearing beds the series aggregates 
only 1760 feet, a thickness quite comparable to that of the 
type-locality of the Temblor. Other localities are known in 
which the beds referable to the Temblor attain a much greater 
thickness than any here given. Elsewhere a statement has 
been given of the criteria upon which a provisional division 
of these beds might be attempted. 
In the outer Coast Ranges of California are beds that have 
been described and classed under the undefined name of 
“Vaqueros.” Without recognizing the sufficiency of this 
rambling and nondescript name, it may be said that most, if 
not all, of the strata that have hitherto been classed under this 
term are comparable stratigraphically and faunally to the 
Temblor. Dr. Arnold has described beds in the Santa Cruz 
mountains, and Dr. Fairbanks in the Coast mountains about 
San Luis Obispo that are referable to the Temblor. Dr. 
Merriam has pointed out that Turritella hoffmani is found 
