ROCKS OF THE COAST RANGES OF CALIFORNIA 499 
quite like those of the San Pablo formation, in the Mount Diablo 
quadrangle. It is, therefore, likely that the Corral Hollow 
plant remains represent a somewhat older horizon than those 
collected near Kirker Pass. 
ANALYSES OF RHYOLITIC TUFF FROM THE SAN PABLO FORMATION, 
BY WILLIAM VALENTINE. 
No. 339. No. 345- 
Near base of Near top of 
San Pablo San Pablo 
SHOS) ocosulosodn doe bom sooo ocouDBUG Ado GOO DOENNODOdK 63.28 63.28 
CEOS eee s 4 Bio bate a Ord FIO IS EEO. M IDI NO cRCIRCROTS Urcieceiore ako ir 1.90 1.18 
ISSO) ogoddoos acoboebeoouddoo co UConG ODDOOO uO ODRO MOON 2.44 0.78 
INeisO) ogo cedbarobcvatposad docu oda don Goon od abu 1.82 0.56 
The Merced formation of Lawson,? which has been referred 
to, is probably younger than the San Pablo and of Upper 
Pliocene age. The Merced formation is named from Merced 
Lake, in the vicinity of which the beds are extensively devel- 
oped. It is probably identical with the Wild: Cat series of 
Humbolt county, described by Lawson,*? in which case the 
latter name should be dropped. As pointed out by Lindgren,? 
the correlation by Lawson on the Merced series with the 
Auriferous gravels formation is probably incorrect. Ihe sis) atghe 
more likely that the Auriferous gravels series is in part con- 
temporaneous with the San Pablo formation, and in part older 
than that formation. 
H. W. TurRNER. 
* Bull. Dept. Geo!. University of California, Vol. I, pp. 142-149. 
2 Bull. Dept. Geol. University of California, Vol. I, pp. 255-263. 
3Jour. GEOL., Vol. IV, pp. 904, 905. 
