188 The Ohio Journal of Science [Vol. XVII, No. 6, 



The same statement may be made regarding the Springfield 

 dolomite. It also has not been identified west of New Paris 

 nor south of Cedarville. Where the pike crosses the creek, 

 half a mile w^est of Port William, fourteen miles south of 

 Cedarville, the lower strata belonging to the dolomitic Niagaran 

 series no longer can be identified definitely as Springfield. 

 The Springfield dolomite is regarded as a lithologic phase of the 

 dolomitic Niagaran series. Similar fine-grained strata, but not 

 so well bedded, are known also higher in the section. The 

 Euphemia dolomite is regarded as inaugurating this dolomitic 

 series, and the term Durbin formation is proposed, to include 

 them all: the Euphemia, Springfield, and Cedarville dolomites. 

 Durbin is a railroad station about a mile west of the Mills 

 quarries which are located south of the railroad from Spring- 

 field to Troy, about a mile southwest of Springfield, Ohio, and 

 the exposures here form the type section. The Springfield and 

 Cedarville dolomites are well exposed also immediately northeast 

 of Durbin. 



The Laurel limestone, containing Pisocrinus gemmiformis 

 and Stephanocrinus, is represented by typical exposures at 

 New Paris, Ohio. At the Carl quarry, three miles southwest of 

 Lewisburg, near Brennersville, there is another typical exposure, 

 containing the same fossils. East of this locality, the Laurel 

 limestone is identified only stratigraphically, the name being 

 employed for those strata which intervene between the Osgood 

 clay and the base of the Euphemia dolomite. 



In the vicinity of Osgood, and southward in Indiana and 

 Kentucky, the Osgood formation consists of a clayey section, a 

 relatively thin limestone, frequently fossiliferous, and a second 

 clay section, also thin, and occasionally also fossiliferous. The 

 characteristic Osgood fossils occur chiefly in the Osgood lime- 

 stone, but, locally, are abundant also in the upper parts of the 

 lower Osgood clay and in the lower part of the upper Osgood 

 clay. Even the characteristic cystids, described by S. A. Miller 

 as species of Holocystites, are found in the lower part of the 

 upper Osgood clay (21st Ann. Rept. Indiana Geol. and Nat. 

 Resources, 1897, pp. 248, 252, 254, 257), demonstrating that 

 this upper clay should be referred to the top of the Osgood and 

 not to the base of the Laurel section. Fossils occur at this 

 horizon at several localities between Madison and New Marion, 

 Indiana. 



