STREPOMATID^. 251 



Adams. Strepoma, Raf.) Shell generally lengthened conical, 

 with elevated spire ; aperture moderate, produced into a short 

 spout or canal in front ; columella not callously thickened. 

 Distr — 84 sp. Ohio, Tennessee and Alabama Rivers and their 

 tributaries. P, canaliculata, Say (Ixxi, 8). 



GoNiOBASis, Lea. 



Syn. — Melasma, Juga, Megara ( sp.), Elimia, H. and A. Adams. 



Distr. — 274 sp. United States, east of the Mississippi River, 

 California and Oregon. G. impressa^Ijea, (Ixxi, 9). G. Boykin- 

 m?ia, Lea (Ixxi, 10). G. Virginicaj Say (Ixxi, 11). The genus 

 does not occur recent in the elevated region west of the 

 Mississippi. Fossil, Laramie beds — ; Western U. S. 



Shell heavy, ovate or elongated ; aperture somewhat angulated 

 in front, but neither notched or canaliculate. 



EURYC^LON, Lea. Shell obovate, heav}^, nodosely angled ; 

 aperture large, ear-shaped ; columella oval, subtruncate. 10 sp. 

 E. Tennessee, N. Alabama. G. Anthonyi, Budd (Ixxi, 12). 



Pyrgulifera, Meek. 



Distr. — Cretaceous; Wyoming T., U. S. P. /iwmerosa. Meek 

 (Ixxi, 13). 



Spire produced ; whorls shouldered and nodular ; aperture 

 subovate, faintly sinuous, a little produced, but not notched or 

 distinctly angular below ; columellar lip a little callous below, 

 thickened throughout. Very closely allied to the Melanian 

 genus Tiara, Bolten. Dr. C. A. White considers Paramelania, 

 E. A. Smith (== Tiara), synonymous ; it includes three species 

 living in the African lake Tanganyika. 



Cassiopella, White, 1878. 



Distr. — C. turricula, White. Fossil, Laramie beds; Western 

 U. S. 



Shell turriculate, the whorls angulated in the middle. Differs 

 from Goniobasis in being limbilicated. 



ScHizosTOMA, Lea. 



/St/n.—Schizocheilus, Lea. Gyrotoma, Shuttleworth. Mela- 

 toma, Anthony. Apella, Mighels. 



Distr. — 26 sp. Coosa River, Alabama. S. habylonicum, Lea 

 (Ixxi, 14-16). 



Shell conical or fusiform; aperture large, ovate, obtusely 

 angled below ; outer lip with a posterior, sutural sinus or fissure ; 

 columella smooth, incurved. 



Anculosa, Say. 

 Si/n. — Anculotus, Say. Ancylotus, Ilerm. Leptoxis (Raf?), 

 Hald. 



