DUNKARD FOEMATION 107 



long sections in Monroe county of Ohio. The remarkable persistence of 

 this limestone bed, so much in contrast with the limited extent of all 

 other beds below, makes it not improbable that it may be that in the 

 Maryland area which Doctor Martin has correlated with the Jollytown. 

 The interval there is 238 feet above the Washington coal bed. The lime- 

 stone in Pennsylvania and West Virginia is almost unmistakable, the 

 color being a peculiar blue and the associated shales, black. It is oLU'ii 

 thin, but increases southwardly, so that beyond the Pennsylvania line it 

 has sometimes 10 or 15 feet of limestone and calcareous shale, and at 

 almost the last exposure in Jackson county at the south the mass is almost 

 30 feet. 



The coal horizons are unimportant. 



The Boyd coal bed refers not to a bed, but to a horizon. In the in- 

 terval between the Upper Washington and Ten-mile limestones one finds 

 oftentimes a coal streak, now almost on the lower limestone, again almost 

 directly under the upper, and occasionally almost midway, the last con- 

 dition being in localities where the interval between the limestone is 

 greatest. The deposits can hardly be contemporaneous, but the interval 

 is a small one and they may overlap in time. The name is taken from 

 Boyd run, in Greene, the only place at which the coal is of workable 

 thickness. A coal at this horizon is in West Virginia just south from the 

 state line, where it rests on the Upper Washington. The term Pursley 

 coal bed is used in the same way, to designate a coal horizon between 

 Ten-mile and Eogersville limestones, an interval in which isolated de- 

 posits of coal occur at numerous localities. 



The Dunkard coal bed (J. J. Stevenson, 1876), a thin but very per- 

 sistent bed in western Greene, is absent from Washington and it was not 

 recognized in the northern border of Greene county. It is not present 

 in eastern Greene. The bed is rarely more than 2 feet thick, but is 

 double and, like some of the lower beds, is associated with a plant- 

 bearing shale. Though very thin, it is of much local importance, as it 

 yields good coal. In the southwest corner of Greene, it is about 125 

 feet above the Jollytown coal. A trace of coal found by Doctor White 

 on the Ohio river, in Tyler county, at about 100 feet above the bed al- 

 ready taken as the Joll)rtown, may be at the Dunkard horizon. Another 

 coal bed, apparently that termed the Hostetter by Doctor White (1891), 

 is in the interval between the Dunkard coal and Mneveh limestone, at 

 about 40 feet below the latter. It is present in Springhill, Aleppo, Eich- 

 hill, and Morris townships of Greene. A coal in this interval is shown 

 in Wetzel of West Virginia. 



