18 



PLANORBIS LENTUS, Say. 



Plate 3.— Figs. 4—6. 



P. testa opaca, utrinque angulata; superne profunde um- 

 bilicata; subtiis anguste excavata: anfractibus 4 — 5 crassis, 

 ultimo sinistrorsum extendens: aperturi\ longula. 



SYNONYMS AND REFERENCES. 

 P. LENTUS, Say. Am. Conchology, pi. 54, fig. 1. 



DESCRIPTION. 



Shell dense, wide, and compact, composed 

 of four or five coarsely striated, convex whirls, 

 of which the last one, as it approaches its ter- 

 mination, deflects to the left, so that the right 

 portion of the labium leaves about one-third of 

 the penultimate whirl to the right of it, the 

 aperture or labium meeting the remaining two- 

 thirds: aperture extended in front, and in con- 

 sequence of the lower carina, having an angle 

 near its junction with the labium: sutures dis- 

 tinct: cup of the left side narrow, and rather 

 deep. 



Color yellowish-brown. 



Geographical Distribution. Found in the 



