332 J. J. Stevenson — Use of the Name " Catskill." 



This case is very similar to that in hand. The problem is to 

 give a name to the series of rocks between two sufficiently 

 well defined limits, the Hamilton below and the Pocono above. 

 The series in all its parts is practically persistent for fully six 

 hundred miles along its easterly outcrop, from within a few 

 miles of the Tennessee border through Virginia, Maryland, 

 Pennsylvania and New York into the Catskill Mountains. 

 Sections taken at short intervals show remarkable resemblance 

 in detail, remarkable uniformity in the more important beds 

 until within a short distance of the New York line, where 

 the lithologic features hitherto characterizing only the highest 

 members of the sections extend lower and lower until, in the 

 Catskill Mountain region, they become almost equally charac- 

 teristic of the lowest members. As the writer has shown for 

 northern Pennsylvania along the State line by comparison of 

 sections made by White, Ashburner and Sherwood and, as 

 was shown by Hall and now also by Darton for southern New 

 York, the same condition is observed in coming eastward 

 toward the Catskill region. Recognizing this condition, but 

 seeming to regard its discovery as new, Mr. Darton says : 



" As the Catskill in its type region comprises Portage and 

 Chemung, my proposition now is to discontinue the use of 

 Catskill as a coordinate formation term and use the term Cats- 

 kill group to include the Portage and Chemung formations, 

 the latter extending to the base of the Lower Carboniferous. 

 I believe the Chemung and Portage are formations distinctly 

 separable over a wide area, but Chemung and " Catskill" as 

 formations are only separable by a lithologic distinction, which 

 progressively varies several thousand feet in stratigraphic posi- 

 tion in the extension of the beds across southern New York."* 



This is now no mere strife about words ; possibly were the 

 name to be given de novo, the case might be different. But 

 this is no beginning ; the three groups, Portage, Chemung 

 and Catskill have been recognized for forty years ; they are 

 recognizable as separate in an immense area, compared to 

 which the Catskill Mountain region of New York is utterly 

 insignificant. A lithologic distinction between Chemung and 

 Catskill was not the basis on which the groups were separated 

 in the typical locality of the latter, which is Susquehanna 

 County of Pennsylvania! and no such distinction can be used 

 with safety. That feature, however, was used in other locali- 

 ties, by Yanuxem himself as well as by other observers, in 

 order to determine equivalence. This test led to Prof. Hall's 

 placing of the Lower Chemung near Blossburg, Pennsylvania, 

 into the Old Red Sandstone and therefore to regard the 



* Darton. loc. cit., p. 209. 



f Vanuxem in Assembly Doc. No. 50, 1840, p. 381. 



