460 THE JOURNAL OF GEOLOGY. 
Acanthoceras, aff. naviculare, Mant. Fulguraria gabbi, White. 
Pachydiscus, aff. denisonianus, Stol. Globichoncha remondi, Gabb. 
Gaudryceras, aff. timotheanum, Mayor. Gyrodes conradiana, Gabb. 
Gyrodes pansus, Stol. 
Lytoceras, conf. jukesi (Sharpe) 
Whiteaves. Gyrodes, sp. 
Phylloceras ramosum, Meek. Margaritella globosa, Gabb. 
Scaphites, sp. a. : Avicula nitida, Forbes. 
Scaphites, sp. b. Cardium remondianum, Gabb. 
Schloenbachia chicoensis(Trask) Gabb Chione varians, Gabb. 
Schloenbachia inflata, Sow. Cucullza truncata, Gabb. 
Schloenbachia propinqua, Stol. Cyprimeria lens, Gabb. 
Schloenbachia, conf. serrato-carinata, Exogyra, sp. 
Stol. Exogyra, sp. 
Schloenbachia, sp. Homomya concentrica, Gabb. 
Nautilus, aff. rota, Blanford. Inoceramus labiatus, Schloth. 
Baculites, sp. Inoceramus, sp. a. 
Hamites, sp. Inoceramus, sp. b. 
Heteroceras, sp. Meretrix nitida, Gabb. 
Actezonina californica, Gabb. Modiola siskiyouensis, Gabb. 
Anchura californica, Gabb. Ostrea, sp. 
Anchura falciformis, Gabb. Pectunculus veatchi, Gabb. 
Cinulia obliqua, Gabb. Pectunculus sagittata (?), Gabb. 
Cinulia, sp. Pinna brewerl, Gabb. 
Dentalium stramineum, Gabb. Tellina parilis, Gabb. 
Euspira, aff. pagoda, Forbes. Teredo, sp. 
Fulgur hilgardi, White. Trigonia evansana, Meek. 
STRUCTURE. 
Sections. —The section shown in Fig. 1 is approximately in the 
direction of the dip drawn through the vicinity of the ’49-Mines 
ina northeasterly direction. Toward the western end, as has 
been said, the Cretaceous strata rest directly upon the aurifer- 
ous slates, and dip more nearly toward the north, at an angle of 
30°. In the bottom of the valley they are covered by Pleisto- 
cene deposits, but appear again where the erosion of Bear Creek 
has exposed them. From this point, one travels across the 
upturned edges of the beds to near the summit of the mountain. 
The dip is pretty uniform for the greater part of the section, but 
toward the eastern end it is somewhat less steep. 
Just east of Bear Creek the first low range of hills is formed 
