86 THE DEVONIAN AND CARBONIFEROUS. [bull. 80. 



The same author 1 determined the age of certain footprints from the 

 red shale near Mount Carbon. 



Ancient footprints discovered by Mr. Isaac Lea in the "Bed Shale" 

 at Mount Carbon, in Pennsylvania, and assigned by him to the Devo- 

 nian period, were considered by the author to belong in reality to the 

 "Reds" of the Carboniferous, a few hundred feet below the productive 

 coal series. They are accompanied by a series of similar footprints at- 

 tributed to batrachian reptiles, trails, prints of some unknown four- 

 toed animal apparently reptilian, and trails analogous to those of 

 worms and mollusca. The larger footprints are mainly five-toed, alter- 

 nate in the steps, and nearly equal in size. 



In 1856 Mr. J. P. Lesley reported on the Broad Top coal basin. 2 



The Broad Top coal basin, situated between Huntingdon and Bed- 

 ford Springs, was imperfectly reported upon in 1838 by Mr. McKinley, 

 the substance of the report appearing in the annual reports of the Geo- 

 logical Survey. 



In 1855 the author made a more complete survey of this region, cov- 

 ering about 80 square miles, established the levels of over niue thou- 

 sand points, and reached the following conclusions : (1) That the suc- 

 cession of the measures is not different from the system made out iu 

 western Pennsylvania and eastern Ohio. (2) That the structural re- 

 sults lead to the conclusion that the abruptness of the anticlinals could 

 be produced only by side pressure. (3) That the Precarboniferons 

 Coal Measures are represented in this region by beds of black slate 

 containing little coal, the Subcarboniferous limestone being present in 

 small amounts. 



J. P. Lesley, 8 remarking on the Subcongloraeratic Coal Measures of 

 northwestern Virginia, thinks those beds represent early Carbonifer- 

 ous formations, such as are seen in Ireland, Scotland, and possibly in 

 Melville Island. Similar beds occur in southern Virginia, in south- 

 eastern Kentucky, and in Nova Scotia. The lowest Devono-Carbouif- 

 erous slate represents a still earlier period, and may be correlated with 

 the German Devonian Coal Measures. 



Mr. J. M. Hale 4 (1864) reported at the junction of the Beaver Dam 

 and eastern branches of Clearfield Creek, a boring of 548 feet. At the 

 depth of 199 feet a vein of coal 4 feet 4 inches in thickness was reached. 

 This is probably in the author's view the same vein as at Osceola or 

 Phillipsburg. 



Mr. B. S. Lyman, 5 in 1867, commenting on the Great Carboniferous 



' Rogers, H. D. : On the position and character of the reptilian footprints in the Carboniferous Red 

 Shale formation of eastern Pennsylvania. Proc. Am. Assoc, vol. 4, 1850, pp. 250-251. 



'Lesley, J. P. : On the Broad Top coal basin in central Pennsylvania. Am. Assoc, vol. 10, pt. 2, 

 1856, pp. 78-81, map. 



3 Lesley, J. P.: On the Subconglomeratic or false Coal Measures of West Virginia and Pennsylvania. 

 Am.Phil.Soc, Proc, vol. 7, 1860, p. 294. 



4 Hale, John M. : Record of an old salt boring in Clearfield County, Pennsylvania. Am. Phil. Soc, 

 Proc, vol. 9, 1865, pp. 459 -460. 



6 Abstract on the Great Carboniferous conglomerate in Sullivan County, Pennsylvania. Phil. Acad. 

 Sci, Proc, vol. 19, 1867, pp. 125-127. 



