36 



Bryant Walker 

 Genus EURYC^LON Lea, 1864. 



Shell large, obovate, thick, solid; spire short; body- whorl 

 large; columella callously thickened above, incurved below and 

 subtruncate. 



Type: Anculosa anthonyi Budd, fig. 127. 



Genus PLEUROCERA Rafinesque, 1818. 



Fig. 127 



Fig. 128 



Shell usually lengthened, conic or 

 cerithiform, spiral, dextral, imperfor- 

 ate; smooth, tuberculate, spirally stri- 

 ate or carinate; aperture moderate, 

 subrhomboidal, prolonged into a short 

 ca,nal below; columella smooth, twist- 

 ed, not callously thickened; lip sim- 



Fig. 129 

 pie, sharp, sinuous, somewhat expanded. 



Type: P. acuta Raf., fig. 128. Radula, fig. 129. 



Section STREPHOBASIS Lea, 1861. 



Shell smooth, spire rather short, obtusely conical, body-whorl 

 MlliMiM] subcylindrical ; aperture subquadrate ; columella thickened below, 

 twisted and drawn back, base subcanaliculate ; lip acute, very 

 sinuous. 



ig- 130 Xype: Melania plena Anth., fig. 130. 



Genus GONIOBASIS Lea, 1862. 



Shell medium size, dextral, spiral, imperforate; smooth, lon- 

 gitudinally plicate, transversely striate or tuberculate; thick, 

 solid, ovate-conic to elongate turreted; aperture subrhomboidal, 

 subangular at the base but not canaliculate; columella smooth, 

 not twisted ; lip simple, acute. 



Fig. 131 



1^^ 



Fig. 132 

 Type: G. oscitlata Lea, fig. 131. Radula, G. dcpygis (Say), fig. 132. 



