California Tertiary Formations.—Hershey. 309 
5. Stratified fine and coarser tuffs of dark red color, tilted at a 
high angle. 
6. Light red beds of coarse debris of pink granite, lava, etc. 
7. A coarse, roughly stratified dark red tuff containing fragments 
of black lava. 
The last bed is very thick. Its general appearance is like 
the red tuffs of the Escondido series. Indeed all the members 
from No. 3 to No. 7, inclusive, are strongly suggestive of the 
Escondido series. They dip away from, and seem 
to rest unconformably upon the massive _ rhyolytes 
which are typically Rosamond. This only confirmed a sus- 
picion which I had before that the Rosamond and Escondido 
series are of about the same age, but that the former is slight- 
ly the older and furnished the material for the fine-textured, 
supposed rhyolyte tuff stratum under the basic lava of Tick 
canyon. 
Remnants of a later Series occur in Mohave river valley 
at several points, notably along the railroad about one and 
one-half miles east of Barstow. The following section, in de- 
scending order, of a bluff just north of the railroad, is typical 
of the series: 
Type-Section of Barstow Series near Barstow. 
Thickness. 
1. Stratified, hard brown material due to arid conditions but 
composition not determined; persistent stratum over a 
CUMS ADEM ATCA corer meta a crijecicc es seek cece mee ts 20 feet. 
Sam Rellony T ANG eit: er ay Silt. wach iettercet tet Sa eietales bu crebls 4 feet. 
3. Stratified, fine gravel and sand of dull red color and con- 
taniier stech, lavas TAGIIENES. mo tose crcl: octasicie oid loc, tae 15 feet. 
4. Structureless bed of white tuff with angular and subang- 
ular fragments of various other rock species embedded 
Meena PN at ee eat Sere eine fee ote 20 feet. 
Tipsy ea: Cohn Se a ISA BAD hb OL: SOE ea ae Se ea 50 feet. 
This formation is extensively developed on the low hills 
on the north side of the valley between Barstow and Daggett. 
It is thin, overlies unconformably the earlier series, and re- 
mains generally in a horizontal position but has been ex- 
tensively eroded. It is a valley formation made under arid 
conditions. In a small railway cutting near the bluff where 
the above was taken, this series is locally much broken up and 
overlaid unconformably by 20 feet of the rearly horizontal, 
