526 CHARLES S. PROSSER 



Coneinaugh formation, or just above the top of the Allegheny, where my 

 studies in 1884 first placed it, instead of near the base of the Allegheny, to 

 which position Dr. David White has assigned it on the basis of fossil plants^ 



Dr. I. C. White also states in this paper that in the red-shale 

 belt of the Conemaugh formation 



occurs an important fossiliferous limestone horizon, the " green Crinoidal 

 limestone" of the Pennsylvania series, which has been traced from central 

 West Virginia northward to the Pennsylvania line and through southwestern 

 Pennsylvania into Ohio [where it is known as the Ames limestone] and across 

 that state without a break to where it re-enters West Virginia again at Hunt- 

 ington.^ 



And finally he states that "the Pittsburg coal is found in the 

 summits of the hills only two miles north from Charleston," 

 W. Va.3 



Recently Dr. David White is reported to have said that : 

 The further study of the floras indicates not merely that the middle of 

 the formation [Kanawha] may be of Mercer age, but that beds up to within 

 125 feet of the " Black Flint" are clearly referable to the latter group, while 

 the basal Allegheny time boundary is probably very much nearer the level 

 of the Black Flint."'' 



For a further discussion of this subject, by Dr. I. C. White, 

 especially regarding the horizon of the Kanawha black flint, see 

 the W. Va. Geol. Surv., Vol. 11, July, 1903, p. 501 and other 

 pages. 



For an explanation of the adoption of "Dunkard," " Monon- 

 gahela," "Conemaugh," and "Allegheny" as formation names 

 in Ohio, see a former paper by the present writer. ^ 



Dr. I. C. White prefers to consider these terranes as series, 

 and writes me as follows : 



I think the term " series" better describes the different divisions of the 

 Carboniferous system, like Dunkard, Monongahela, Conemaugh, Allegheny, 

 Pottsville, etc., and have so used it in my coal volume.* 



8. So far as the writer is aware, the name " Pottsville con- 

 glomerate" did not first appear over the name of Professor 



^ Ibid., Vol. XIII (1902), p. 122. "^ Ibid., p. 123. ^ Ibid., p. 124. 



4 Mendenhall's Report of the 144th Meeting of the Geological Society of Wash- 

 ington, Science, N. S., Vol. XVII (June 12, 1903), p. 942. 



^Am.four. Set., 4th ser., Vol. XI (1901), pp. 191-200 and in particular p. 199. 

 * Letter of April 2, 1903. 



