154 The American Geologist. March, 1892 
2. The metamorphic rocks of the Coast Ranges are pre-Cre- 
taceous. 
3. The Coast Ranges and Sierras are a unit as regards time of 
the main upheaval and metamorphism. 
4. The upheaval and metamorphism of the Coast Ranges as well 
as Sierras is pre-Cretaceous,and consequently the slates of the 
gold belt cannot be considered Cretaceous. 
». The presence of pre-Cretaceous eruptives in the metamor- 
phics of the Coast Ranges. 
6. The serpentine is an altered eruptive and post-Neocomian 
(Knoxville). 
7. No great non-conformity exists between the Knoxville and 
Chico beds. 
The Coast Range system of mountains consists of a series of 
parallel ranges having an average width of seventy miles and a 
length of over four hundred. These extend parallel to the Sierre 
Nevadas and are separated from them by the Sacramento and’ 
San Joaquin valleys. At the opposite ends of these valleys 
the two systems of ranges unite, in Shasta county on the north 
and in Kern county on the south. 
The Sierras. consist in general terms, of a core of granite 
flanked, particularly on the west, by a great width of metamor- 
phic rocks, consisting of slate and crystalline schists. Granite 
occurs also through the Coast Ranges, but usually in small areas, 
not arranged along one regular line of upheaval. The metamorphic 
rocks of the Coast Ranges, though including a large amount of 
slate, mica, and hornblende schists, are distinguished particularly 
by a silicious character. Sandstone, jasper, green quartzose 
schist, and banded flinty rocks are abundant, and are character- 
ized, over large areas, by a wavy structure in the thin bedded 
varieties, and a secondary silicification in which the rock has been 
filled with a network of minute quartz veins. 
Unmetamorphosed strata of undoubted Cretaceous and Ter- 
tiary ages, occur on the flanks of the metamorphic rocks, becom- 
ing particularly prominent through the middle Coast Ranges. 
It was my purpose to determine, if possible, from a lithological 
and stratigraphical standpoint, the relation of the metamorphic 
rocks of Shasta county (the age of a portion of which was 
known, and believed to represent the northern extension of the 
