Vor. 111] ANDERSON—NEOCENE DEPOSITS OF KERN RIVER 91 
point north of the Kern River. Conglomerates, sandstones, 
and ashy beds make up 350 to 600 feet of the series to the 
north of the Kern River. On the flanks of the granite along 
Comanche canyon, beds of coarse sand and conglomerate 
make up 250 feet or more; but it is probably not all exposed. 
Gravelly or pebbly beds can be followed southward to the 
Tejon valley, but positive statements cannot now be made 
concerning them. 
In the outcrop the basal member is not always visible, but 
between Poso Creek and White River, where it is exposed, 
it consists chiefly of coarse arkose sand mingled with rhyolite 
ash. The lowest bed, 250 feet in thickness, is a coarse white 
quartz sand, usually unconsolidated, though locally becoming 
indurated to quartzite. 
Above this is a characteristic aggregate of beds 350 feet 
thick, in which ash is much more conspicuous, and strata of 
ashy sand alternating with beds of white ash in which grains 
of quartz and dark mica form a minor part. Some of the 
beds are entirely of ash of a faint dirty green color, yielding 
reluctantly to erosion, and for that reason forming the capping 
of prominent narrow ridges with bold eastern escarpments 
between the drainage lines. 
Between Poso Creek and the Kern River, where combined 
faulting and erosion have exposed the lower beds, there are 
basal conglomerates and concretionary sandstones near 500 
feet in thickness, mainly detrital, in which ash is not prom- 
inent, though probably not absent. These beds are best 
exposed in Pyramid Hill where they are quite fossiliferous, 
containing many species of marine invertebrates, and the teeth 
and bones of many vertebrate species. 
To the south of the Kern River these basal beds are not 
much exposed, or, if exposed, were not recognized beyond a 
limited distance. It is evident that as the basal beds are 
followed northward they lose more and more their detrital 
aspect, and become more and more ashy and at the same time 
less fossiliferous. 
To the north of Poso Creek, marine fossils are to be found 
in many places in these lower beds, though they are not 
abundant. Immediately below, however, and sometimes in, 
the more ashy beds, the teeth and bones of marine vertebrates 
