442 Prosser — Stratigraphic Position of Tlillsboro Sandstone. 



gully, lie a little lower than opposite the base of the massive 

 layer (No. 4) at the top of the quarry. The top of the massive 

 layer (No. 4) at the top of the middle quarry, according to one 

 reading of the barometer is 5 feet, and as leveled by Mr. Cot- 

 tingham 6 feet, lower than the top of the 11-inch porous layer 

 (No. 7) of the road section, which it resembles lithologically. 

 The 9-inch brownish, porous limestone (No. 8) of the road 

 section, perhaps might be united with the underlying 11-inch 

 layer, and then above this limestone zone is a covered interval 

 (No. 9) of 4 feet 6 inches before the base of the exposed upper 

 layer of Hillsboro sandstone (No. 10) is reached. It is very 

 possible that more or less of this covered interval may belong 

 in the sandstone zone. At least it appears probable that the 

 zone of loose blocks of sandstone to the west of the highway 

 represent the continuation of this upper zone of the Hillsboro 

 sandstone, and stratigraphically below it is the middle quarry 

 of limestone containing Monroe fossils. 



The fossils collected in the Monroe dolomite of Quaker Hill 

 have been studied and identified by Miss Rose Gormley, who 

 is making a thorough study of the entire Monroe fauna of 

 Ohio, and are concurred in by the writer. On the highway in 

 No. 12 of that section, which is above the Hillsboro sandstone, 

 the following species were found : 



1. Hindella f ( Greenjieldia) luhitfteldi Grabau. This spe- 

 cies was identified by Whitfield as Meristella bella* and is 

 reported by Grabau as " Common in the Greenfield dolomite 

 at Greenfield, Ohio." f 



2. Hindella ?( Greenjieldia f ) rotunda ta (Whitfield) Grabau. 

 This is apparently the species that was identified by Whitfield 

 as JSfucleospira rotuvdata from Greenfield, Ohio, and is listed 

 by Bassler as Whitfieldella rotundata.% Grabau states that 

 " The species described by Whitfield occurs in the Greenfield 

 dolomite of Greenfield, Ohio, where it has been obtained as 

 external and internal molds, often indistinguishable from, the 

 internal molds of Hindella (f ) whitfieldi, the originals from 

 which Whitfield's descriptions were made have not been seen, 

 and none of the specimens from Greenfield, Ohio, in the col- 

 lection of Columbia University show the characters of this 

 species." § The specimens are all in the form of external or 

 internal impressions in which condition it is difficult to sepa- 

 rate the two species ; but part of the specimens are ventricose 

 with strongly incurved beaks, which are the most important 

 distinguishing characters given for this species. 



* Ann. N. Y. Acad. Sci., vol. v, p. 510, pi. V, figs. 8-10, 1891 ; and Report 

 Geol. Surv. Ohio, vol. vii, p. 412, pi. I, figs. 8-10, 1893. 



f Michigan Geol. and Biol. Survey, Pud. 2, Geol. Ser. 1, p. 149, 1910. 



i U. S. National Museum, Bull. 92, vol. ii, p. 1380, 1915. 



§ Michigan Geol. and Biol. Survey, Pub. 2, Geol. Ser., 1, p. 151, 1910. 



