GASTROPODA— EUOMPHALIDJE. 



653 



XLVIII. Solenospira Ulrich. 

 Small shells differing from Hormotoma in the small apical angle, 

 the compressed character of the whorls, the surfaces of which 

 are mostly flattened and divided by a prominent median band, de- 

 pressed between sharp spirals, with or without other ridges ; mouth 

 without slit. Ordovicic-Mississippic (?). 



155. S. prisca (Bill.). (Fig. 893, c.) 

 Apical angle about 14 ; shoulder 



and body flat or gently concave ; band 

 wide, carinas prominent, a third carina 

 below the periphery, covered by later 

 whorls. 



Beekmantown of Mingen Islands ; 

 Stones River of Minnesota, Wisconsin, 

 and Tennessee. 



156. S. pagoda (Salter). (Fig. 893, 



4/0 Ordovicic. FlG g93> flf ^ catlidium oehl- 



Differs from the preceding in having erti; c, Solenospira prisca ; d, S. 



an additional carina just below the P a & oda >' <> enlargement of part of 



suture, the lower carina also being 



157 



same. (After Ulrich and Scofield, 

 Pal. Minn.) 



commonly visible above the suture. 

 Black River of Minnesota and Canada. 



S. minuta (Hall). Siluric. 



Minute, apical angle about iy°, shoulder and 

 body gently concave ; carinae only two, sharp and 

 margining the median band. 



Manlius limestone of New York ; Lower (and 

 Upper ?) Monroe of Michigan. 



158. S. (?) turritella (Hall). 



Fig. 894. 

 Solenospira ? 

 turritella. (After 

 Whitfield, Am. 

 Mus. Nat. Hist. 

 Bull. ) 



(Fig. 894.) 



Mississippi. 

 Small, slender, with narrow shoulder and two or 

 more spirals below the band. 

 St. Louis (Spergen) of Indiana. 



Family Euomphalid^e de Koninck. 

 XLIX. Straparollina Billings. 

 Shell small, spirally coiled, spire low, whorls rounded, umbilicus 

 of moderate width. Cambric-Ordovicic. 



