92 The American Geologist. August, i8$>4 
of the mountains perhaps represent the dying- out of such 
faults. Though no Cretaceous rocks have been proved to 
overlie the Devonian strata.it is probable that the faulting 
which produced the mountains took place since Cretaceous 
times, for the foothills of Laramie sandstones give evidence 
of parallel faulting and tilting. 
On approaching the watershed of the Rockies west and 
northwest of the region just referred to, the regularity of 
structure largely disappears. The direction and amount of 
dip vary, folds are not uncommon, and the rocks become 
more or less micaceous and metamorphosed ; slates and seri- 
cite schists underlie the quartzites and conglomerates; and 
fossiliferous beds were not observed. The apparent absence 
of eruptive or plutonic rocks is a feature worthy of note in a 
region where faulting has taken place on so huge a scale. 
The evidence of the action of Dr. George M. Dawson's Cor- 
dilleran ice mass is distinct; the time which has elapsed 
since the Ice age has been comparatively short; and the innu- 
merable glaciers of the region represent the shrinking rem- 
nants of the ice-sheet. 
NOTES ON THE GEOLOGY OF THE COAST RANGES 
OF CALIFORNIA. 
By H. W. Turner and T. VV. Stanton, oi the 17. S. Geological Survey. 
The following fragmentary notes were made some years 
ago during the investigation of the quicksilver deposits of 
the Pacific slope by the U. S. Geological Survey. With the 
exception of those given in the notes on Yolo county, all the 
determinations of the fossils have been made by Mr. T. W. 
Stanton, of Washington, I). C. 
The Chico-Tejoh series. 
It was stated by Prof. Whitney and Dr. Gabb that the up- 
per Cretaceous (Chico) beds of California and the Tejon beds 
(now known to be Eocene) are conformable; and Dr. Gabb 
gives a list of species of mollusks said to be common to the 
two formations. In L882 Prof. Angelo HeilpHn* published a 
review of Gabb's work in a paper, "On the age of the Tejon 
rocks of California and the occurrence of ammonitic remains 
*Proc. Phila. Acad. Sci., 1882, pp. 196-214. 
