DESCRIPTION OF SPECIES 261 



52, r. Upper Mercer: Muskingum County, Locality 28, r. Me Arthur 

 limestone: Vinton County, Locality 84, r. 



Genus Sphaerodoma Keyes 



Sphaerodoma brevis (White) 

 PL XV, figs. 22-24 



1881 Soleniscus brevis. White, U. S. Geog. Surveys west 100 Mer. Kept., Vol. 3, 



Supp. Appendix, p. XXVIII, PL 4, Figs. 5a-c. 



Carboniferous: Coyote Creek; north of Black Lake; and near Taos, New 



Mexico. 

 1813 Sphaerodoma brevis. Girty, U. S. Geol. Surv., Bull. 544, p. 201, PL XXIV, 



Figs. 8-12a. 



Wewoka formation: Oklahoma. 



Description. This species appears in the Lower Mercer limestone 

 where it is of rare occurrence, but becomes common in the McArthur 

 limestone. The shell is small, having the low spire with concave sides 

 and the inflated body whorl of White's species. The single fold on the 

 columnella is well shown on some specimens. No essential difference 

 can be noted between this form and Figures 25, 26, and 28 of the West 

 Virginia form designated by Price as Sphaerodoma ? primigenia var. 

 intermedia, 1 which, it seems possible, may prove to be a synonym of 

 White's S. brevis. 



Horizon and locality. Lower Mercer limestone: Perry County, 

 Locality 35, r; Stark. County, Locality 52, c. Upper Mercer limestone: 

 Holmes County, Locality 73, r. McArthur limestone: Vinton County, 

 Locality 84, c. 



Sphaerodoma fusiformis (Hall) ? 



1858 Macrocheilus fusiformis. Hall, Geol. Iowa, Vol. 1, Pt. 2, p. 718, PL 29, Fig. 7. 

 Coal Measures: Alpine Dam, Iowa. 



Remarks. An internal cast of a high-spired gastropod of median 

 size from the Lower Mercer limestone is evidently closely related to 

 this species. On the fragment studied five volutions are present which 

 show the same form and spiral slope as Sphaerodoma fusiformis, but 

 the shell presents insufficient data for satisfactory identification. Sev- 

 eral imperfect specimens from the McArthur limestone are apparently 

 closely related to this species, to which they have been provisionally 

 referred. 



Horizon and locality. Lower Mercer limestone: Perry County, 

 Locality 35, r; Muskingum County, Locality 45, r. McArthur lime- 

 stone: Locality 84, r. 



'Price, W. A., W. Va. Geol. Surv., Preston Co. Report, p. 541, PL XLIII. 



