Prosser — Stratigraphic Position of Hillsboro Sandstone. 443 



3. Leperditia ohioensis Bassler. This is the species which 

 Whitfield identified as L. alta from Bellevue, Sandusky 

 County, Ohio, and Grabau in 1910 renamed L. altoides, and 

 gave for additional distribution the " Greenfield dolomite of 

 Greenfield and Ballville, Ohio."* The name of L. altoides, 

 however, was given by Weller in 1903 to a species in the 

 Decker Ferry formation of New Jersey f and on account of 

 this preoccupation Bassler has renamed the Ohio specimens L. 

 ohioensis.% 



In the field on the Mrs. Ellen Burns farm, in No. 5 of that 

 section, a few rods to the west of the road, and apparently 

 stratigraphically above the Hillsboro sandstone, the following 

 species were collected : 



1. Ilindellaf ( Greenfieldia ? ) rotundata (Whitfield) Gra- 

 bau. 



2. Rhynchospira prceformosa Grabau. 



These specimens are apparently identical with those from 

 Greenfield, Ohio, which Whitfield identified as Retzia formosa, 

 the species that Hall used as the type for his genus Rhyncho- 

 spira. One of the specimens described by Whitfield is in the 

 Geological Museum of Ohio State University, and it is true 

 that it is smaller than the adult forms of Rhynchospira formosa 

 Hall ; but among the specimens from Quaker Hill are larger 

 ones which it is difficult to separate from medium-sized speci- 

 mens of R. formosa. The type specimens of Rhynchospira 

 formosa Hall are from the New Scotland formation of the 

 Helderbergian series in the Helderberg Mountains of Albany 

 County, New York. The species has, however, been identified 

 by Maynard in the Keyser member of the Helderberg forma- 

 tion in Maryland and West Virginia,§ which is the oldest 

 member of the Helderberg formation of those states, underly- 

 ing the Coeymans member or limestone. Still earlier the 

 species had been identified by Weller in the Decker ferry 

 formation of New Jersey, || which he believed was the southern 

 extension of the Coralline limestone of New York that belongs 

 in the Cayugan series, and has been renamed the Cobleskill 

 limestone. Dr. Swartz of the Maryland Survey, however, cor- 

 relates the Decker Ferry formation with the lower or Chonetes 

 jerseyensis zone of the Keyser member,^[ and this latter corre- 

 lation is apparently accepted by Bassler.** 



* Idem, p. 205. 



f Geol. Surv. New Jersey. Eeport on Paleontology, vol. iii, pp. 63, 252, 

 pi. XXIII, figs. 1, 2. 



\TJ. S. National Museum, Bull. 92, vol. 1, p. 704, 1915. 



§ Maryland Geol. Survey, Lower Devonian, p. 426, 1913. 



I Geol. Survey of New Jersey. Eeport on Paleontology, vol, iii, p. 240, 

 1903. 



^"Maryland Geol. Survey, Lower Devonian, p. 98, 1913. 



**U. S. National Museum, Bull. 92, vol. ii, 1915, pi. 3— Silurian Correla- 

 tion Table. 



