42 Crandall — Santa Clara Valley Region in California. 



The Aucellae here are found both in the pebbles and in the 

 matrix of this conglomerate. This indicates an elevation of 

 the land mass in this vicinity during Knoxville times, with rapid 

 erosion following the uplift. This may mean no more than a 

 local unconformity, in this place, and is representative of near 

 shore conditions. There is a considerable thickness of barren 

 shales, sandstones, and conglomerates interbedded, underlying 

 this fossiliferous conglomerate, which must belong to the Knox- 

 ville. Serpentine is intruded into the Knoxville sandstones at 

 this place. As was found further north near Milpitas, the 

 Tertiary overlies the Cretaceous unconformably. In Alum 

 Rock canyon, several miles south of this place, there is a similar 

 conglomerate, apparently continuous with the Beryessa con- 

 glomerate, but in the pebbles of which no Aucellae have as 

 yet been found. 



Alum Rock Canyon. — The Cretaceous conglomerate of Alum 

 Rock, exposed near the mouth of the canyon, has furnished no 

 fossils, but a fine-grained conglomerate further up the canyon 

 has yielded the following Knoxville forms : 

 Pelemnites, sp. 

 Aucella. Piochi Gabb * 



There are also beds of a heavy massive sandstone which have 

 yielded no fossils. 



The sedimentary beds continue southeast along the base of 

 the Monument Peak range for several miles and then dis- 

 appear. 



Evergreen. — The main mass of the Cretaceous sediments in 

 the ridge between Hall's valley and the Santa Clara Valley are 

 massive conglomerates with large bowlders of quartz porpyhry, 

 and other siliceous igneous rocks. Above this conglomerate 

 there are a few hundred feet of Cretaceous sandstone upon 

 which the Tertiary lies unconformably. Below the conglom- 

 erate is a hard black shale from which Axicella Piochi Gabb 

 was obtained. The exact localit} 7 is a small hill that juts out 

 from the Monument Peak ridge, about one and a half miles 

 southeast of the town of Evergreen. 



Dry CreeJc. — The Dry Creek locality is five miles southeast 

 of Evergreen P. O. The Cretaceous at this place is represented 

 by black sandy shales which are badly crashed near the ser- 

 pentine of the Silver hills. These fossils were found near the 

 Dry Creek road that goes from Evergreen to San Felipe Valley. 

 Aucella Piochi Gabb 

 Aucella crassicollis Keyserling 



* This was termed Aucella mosquensis by Dr. J. P. Smith in his paper on 

 the Age of the Auriferous Slates of the Sierra Nevada, Bull. Geol. Soc. Am., 

 v, 256. Aucella trigonoides was also mentioned from Stevens creek canyon, 

 west of San Jose. Both of these species of Aucella, Dr. Smith has since rec- 

 ognized as being the common Aucella Piochi of the Pacific Coast. 



