316 C SCHUCHERT — LOWER HELDERBKRG-ORISKANY FORMATIONS 



Very difficult to find reliable data concerning this formation to the 

 southwest, and the extract given below is all that the writer has found. 

 W. B. Rogers,* in his description of the several members of the geo- 

 logical series belonging to the region west of the Blue Ridge, thus de- 

 scribes the Oriskanv : 



"(No. 7.) — The sandstones composing this member of the series are, in general, 

 characterized by an open and rather coarse texture, and an extraordinary abun- 

 dance of organic impressions. In color they vary from a yellowish white to a 

 dark greenilh gray. They are usually presented, especially the lighter colored 

 variety, in massive beds of several feet in thickness, and from their frequent 

 occurrence alon«: the flanks and declivities of the ridges, dipping at a steep angle, 

 and hare of vegetation, they form a curious feature in many of the wild scenes 

 among our mountains. . . . 



" Nearly all of the mountains of Hampshire, Hardy, Pendleton, Pocahontas, and 

 Alleghany counties, exhibit extensive and instructive exposures of this rock, which 

 from its whiteness, frequently bare surface, profusion of organic impressions, and 

 disposition to disintegrate into a coarse white sand, is one of the most strongly and 

 uniformly characterized of the members of our series. 



"An iron ore has been found in various places in connection with these strata" 

 (p. 179). 



From Rock Enon Springs, on Great North mountain, in Frederick 

 county, 15 miles northwest of Winchester, in Shenandoah valley, the 

 United States National Museum has received the following fossils col- 

 lected by Mr Geiger, of the United States Geological Survey : 



Spirifer arenosus (Conrad). 15954. Modiomorphn sp. undet. 15958. 



Plalyeems magnificum Hall. 15957. 



From the northwest pike, six miles from Winchester, Spirifer murchi- 

 soni and & arenosus (15955) were collected by Mr Geiger. 



From the drift about Washington, D. C, and Alexandria, Virginia, 

 have been gathered many characteristic Upper Oriskany species, of which 

 those given below are in the United States National Museum. The origin 

 of this drift is unknown, but it must be either from the west or northwest: 



Favosites, ramose form. 18137. Anoplolheca flahellUes (Conrad)* 



Teniaculites acula Hall. 18166. Spirifer arenosus (Conrad). 28105. 



Camarotcechia spedosa Hall. 17494. MyviUirca sp. undet. 18149. 



In southwestern Virginia, near the Tennessee state line, Professor J. J. 

 Stevenson has observed the Oriskany sandstone in a number of places. 

 It is there never more than 40 feet thick, and may repose either on the 

 New Scotland member of the llelderbergian or on the Clinton. It is 



♦ Rept. Geol. Survey Ya. for 1837-'38. From "A Reprint of Ann. Rept. on the Geology of the Vir- 

 ginias," Appleton, 1884, pp. iT'.t, 199. 



