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



" * * * * Toward the southwest (from Lowellville) the forma- 

 tion becomes more and more sparing in its exposures, and thin- 

 ner, until in southwestern Stark County and northeastern Tus- 

 carawas County it disappears, and the Putnam Hill Limestone 

 comes in on nearly the same horizon, but stratigraphically dis- 

 tinct." [Ohio Geol. Sur. Vol. IX, Bull. 4, p. 17-1.] 



From this brief review of the literature on these limestones 

 it is quite apparent that three limestones are recognized in 

 Western Pennsylvania below the Lower Kittanning Coal, and 

 in Ohio four are recognized below the same horizon. In the 

 former state the Lower Mercer and Vanport are the more 

 important stratigraphical horizons; in the latter state the 

 Lower Mercer and the Putnam Hill have that distinction. It is 

 also apparent that uncertainty characterizes the present knowl- 

 edge of the presence and character of the westward extension 

 of the Vanport limestone from eastern Mahoning County, and 

 likewise the eastward extension of the Putnam Hill from Central 

 Stark County. The Lower Mercer is regarded as the unfailing 

 limestone from Mercer County, Pennsylvania, to Zanesville, 

 and as the lowest and earliest limestone in the Lower Coal 

 Measures. The Upper Mercer is conceded to be present in 

 many places, but by no means so regularly present as the Lower 

 Meixer. 



SURFACE, STREAMS, AND ELEVATIONS. 



From central and southern Stark County southwestward, it 

 would appear from the Ohio Reports that these limestones are 

 fairly well known and the same can be said of them on the eastern 

 line of the state. But 'from central Stark County to the Pennsyl- 

 vania line they are not well known. Consequently a somewhat 

 careful examination has been made of this territory covering 

 an extent of about fifty miles. Of the region examined all but 

 a little in southern Stark County is deeply drift covered, and 

 only now and then can the strata be seen to emerge from the 

 drift inantle save along streams and even here long intervals 

 often occur between meager outcrops. 



From west to east the following streams and tributaries 

 have been examined for outcrops of the above limestones: 

 Nimishillen Creek, Mahoning River, Island Creek, Little Mill 

 Creek, Turkey Broth, Meander Creek, McMahon Run, Diehl 

 Creek, Mill Creek, Neff Run, Indian Creek, Yellow Creek, Burgess 

 Run, and Furnace Rvm, all of which are shown on the accom- 

 panying map of Stark and Mahoning Counties. 



Elevation wall be seen to be an exceedingly important factor 

 in obtaining the I'esults of this investigation and it is constantly 

 employed in determinations. The elevations given were ob- 

 tained bv level from elevations indicated in the field bv the 



