Stratigraphy at Slates Sprinr/s. — Fairbanks. 351 
ments of an Inoceranms were found in the ocean cliffs beneath 
the sulphur springs. In 1894 this locality was again ex- 
amined and a collection of five species of molluscs made in 
addition to some poorly preserved plants* It was hoped 
that these would be indicative of some definite geological 
horizon, but all the species were found to be new and uncer- 
tain in their time range, though presenting a Cretaceous 
rather than a Jurassic aspect. One species of Inoceramus 
among the lot appeared to be closely allied to a Cretaceous 
form. The apparent conflict between the stratigraphy and 
the paleontological evidence tended to discredit the correct- 
ness of the field work. The writer had however felt most 
thoroughly convinced from the beginning that there could be 
no doubt about the propriety of referring the strata at Slate's 
Springs to a pre-Cretaceous horizon (Golden Gate series) the 
rocks of which are so widely developed through the Coast 
ranges. These beds are believed to be continuous with the 
older rocks of Pine mountain. During the recent trip this 
mountain was revisited and the marked contrast between the 
Aucella-h(^i\Ymg sandstone and shale, with distinct and reg- 
ular bedding, and the distorted and sheared rocks of the un- 
derlying Golden Gate series was more strongly impressed up- 
on the writer than ever before. About the slopes of the 
mountain the knobs of hard and often silicified sandstone 
project up through the Knoxville presenting the greatest con- 
trast imaginable, with the shales and sandstone of the latter 
formation. In addition to the non-conformity on the south 
side of the mountainf there occur on the north side pebbly 
conglomerates containing abundant fragments of the red jas- 
per which is so plentiful in the Golden Gate series in this 
vicinity. 
The pre-Cretaceous rocks extend continuously northward 
from Pine mountain forming all the western portion of the 
Santa Lucia range as far as Vicente creek. Here the series 
rapidly narrows and for a short distance south of Mill creek 
has an exposed thickness of less than 1,000 feet. At Mill 
creek it is somewhat greater but tlie metamorphism has been 
so intense that it is rather difficult to draw the line between 
*J()ur. of Geol. vol. in, p. 42.3. 
tJour. of Geol. vol. iii, p. •421. 
