128 The Ohio Naturalist. [Vol. X, No. 5, 



feet below the Lower Mercer limestone and 64 feet above the 

 level of the Sharon coal at the base of the shaft. Its position 

 seems to be about the horizon of the Quarkertown coal, but the 

 onty suggestion of an associated coal is a considerable thickness 

 of black shale overlying it, which is quite fissile, fairly tough and 

 lifting in broad sheets particularly the first few feet above the 

 limestone. About one foot of the shale above the limestone is 

 somewhat calcareous responding readily to acid, and suggests 

 that at no great distance it may become limestone. This black 

 shale is in harmony with the gray and black shale with the two 

 thin seams of coal found above the liinestone in the Yellow 

 Creek gorge. 



Being covered the character of the strata immediately 

 beneath the limestone was not seen. A little below, however, 

 massive layers of sandstone appear which are certainly the 

 upper part of the Lower Mas.sillon sandstone, or Lower Con- 

 noquenessing of Pennsylvania. The limestone is black, very 

 hard, tough, and apparently in one layer. It is 2 feet or more 

 in thickness — the full thickness not being obtained due to a 

 sharp dip down stream concealing its base. - It is very fossilifer- 

 ous, the white shells and crinoid stems presenting a striking 

 appearance in the black matrix. A few species of brachiopods 

 and fragments of crinoid stems predominate. The latter are 

 often 6 or 8 inches long, as they also are in the Vanport in the 

 quarry above, and lying horizontally with the section markings 

 showing plainly they somewhat resemble worms, and the unini- 

 tiated point them out and confidently inform one that they are 

 petrified worms. 



Newberry in his report on Mahoning County, and in a section 

 on Grindstone Run indicates the presence at this horizon of a 

 "Dark silicious limestone" 1 foot in thickness. [Ohio Geol. Sur. 

 Vol. Ill, opp. p. 804.] He nowhere else describes or mentions it 

 so far as the writer is aware. 



It will be recalled that a black limestone outcrops in the 

 Yellow Creek gorge at 884 feet above sea. This outcrop is about 

 2\ miles west of Furnace Run, and while it lies 28 feet lower than 

 the outcrop on the latter run it is certainly the same stratum. 



In a test well on the C. T. Geiger farm located near the 

 Youngstown-Boardman pike and about 1 mile north of Board- 

 man Center and 8f iniles due west of the Yellow Creek outcrop, 

 a 3 foot black limestone was reached at 910 feet above sea. It 

 lies 111 feet below the Lower Mercer limestone and 47 feet above 

 the Sharon coal which is 2 feet thick in this well and lies at 863 

 feet above sea. 



It will be recalled that in the Alliance section an unknown 

 limestone of 5 feet thickness was struck at 882 above sea and at 



