CAMBRIAN FOSSILS FROM PIOCHE MOUNTAINS 291 



He further believes that a proper correlation would place the Olen- 

 ellus fauna above the Paradoxides, and therefore at least as high as 

 upper Mid-Cambric.^ Throughout western America the Olenellus 

 zone is preceded by thick quartzite beds, which Matthew believes are 

 equivalent to the Protolenus and Paradoxides zones. Chamberlin and 

 Salisbury state that "in the Hudson- Champlain valley the Olenellus 

 fauna appears to have lived on until the advent of the Dikellocephalus 

 fauna. "^ They consider it possible "that the Olenellus of the West 

 and of the Hudson -Champlain valley may have been contemporaneous 

 with the Paradoxides of the East, " although they incline to the 

 opinion that it was contemporaneous with the Holmia. At Newton, 

 N. J., Mr. Stuart Weller found a supposed Olenellus species in the 

 undoubted Dikellocephalus zone. In speaking of the value of this 

 specimen, he says: 



It suggests the possibility of a much longer range for the genus Olenellus in 

 geologic time than has been ascribed to it. This genus is usually considered 

 as particularly characteristic of the very lowest Cambrian strata, but here it 

 seems to be associated with the fauna which bears unmistakable marks of the 

 upper Cambrian age.^ 



The exact stratigraphic position of the Olenellus zone is not there- 

 fore established. With our present knov/ledge it is impossible to 

 state whether it is Upper or Lower Cambric, but it appears that 

 Walcott's view is supported by the more evidence. The writer has 

 collected several new forms, but they give no further information as 

 to the position of this series. At present, however, we shall adopt the 

 classification of Mr. Walcott. 



In the Pioche Mountains the Lower and Middle Cambric only are 



represented; the Upper has been removed by erosion. Faulting has 



so complicated matters that a continuous section cannot be obtained, 



but one made up from different places is as follows: 



5. Limestone 800 feet 



4. Shale 75 " 



3. Limestone . 600 " 



2. Shale 400 " 



I. Qua'rtzite 1500 " 



^Transactions of the Royal Society of Canada, 1899, Second series, Vol. V., 

 pp. 67, 68. 



^Chamberlin and Salisbury. Geology^ Vol. II, p. 245. 



sGeological Survey of New Jersey, Paleontology, 1902, Vol. Ill, p. 13. 



