74 The American Geologist. February, i«93 
j^nuiite which has been intinided into it. South of the Encinos 
ranch on the northern slope of the Santa Monica range, is an in- 
teresting exposure of rocks. First there are Tertiary sandstones 
(lipping north 25-40 degrees. Under these are the crushed and 
metamorphosed rocks of the oUler series, with stratification 
hardly discernible. Just above the sandstones the older rocks 
are intruded by dioritic granite. There is no sign of the granitic 
rocks having been intruded into the Miocene, and there seems not 
the slightest doubt but wdiat the crystalline and metamorphic 
rocks represent an older pre-Cretaceous formation. I have been 
able to verify none of Prof. Whitney's statements in regard to 
Tertiary or even Cretaceous granite in California. He says of the 
Santa Monica range that granite forms the axis, and that it has 
been intruded into Pliocene sandstones which are much metamor- 
phosed and dip away on either hand.* The real Miocene has been 
confused with the underlying older series, and both classed to- 
gether as rocks of the same period. Prof. Jules Marcou also 
held the opinion that no rocks older than the Tertiar}- existed in 
the Santa Monica range, t The mistake heretofore made is due 
to a confounding of the Tertiarv with the underlying pre-Cre- 
taceous series. In those portions of the report on the Pacific 
railroad survey, and of the general geology of California, Vol. i, 
<levoted to the coast region, this mistake is constantly made. 
The Santa Ana mountains are a spur of the Peninsula range of 
San Diego county. The sedimentary rocks are often l)ut slightly 
metamorphosed, and fossils of proba])le Carboniferous age were 
found in three dift'erent places. One fossil bearing stratum was 
discovered within less than a mile of the granite of Santiago peak. 
It was A'er}' highly metamorphosed, being apparently a micaceous 
felsite. The other fossils were in a dark gray limestone onlj' 
slightly altered. In portions of the range the quartzose rocks 
are filled with a network of small quartz veins xevy closely re- 
sembling the characteristic phenomena of the Coast ranges farther 
north. The fossil l)earing rocks have been intruded by granite 
which forms an integral part of the Peninsula range. 
A glance at a topographical map of California shows two main 
chains of mountains. One extending near the coast the whole 
length of the state ; the other and more rugged one, branching oft' 
*(Teologioal Survey of Cal., Vol. i, ]>. 121. 
tGeof^rapliical Svirveys West of tlie 100 Meridian. 1876. p. 172. 
