Synopsis Fresh-Water Moli^usca 



Section PSEUDOGALBA Baker, 1913. 



Shell as in Galba, but with the inner lip less expanded. Gen- 

 italia in Galba. Lateral teeth tricuspid. 



Fig. 14 



Fig- i.S 



Fig. 16 



Type: L. humilis Say, hg. 14. Radula (L. obnissa Say), fig. 15. Animal 

 ( ibid. ), fig. 16. 



Subgenus STAGNICOLA Leach, 1830. 



Shell varying from elongate to short-ovate; outer lip (usually) 

 somewhat thickened within ; columella distinctly plicate ; inner lip 

 appressed; axis slightly or not all perforate; surface with strong, 

 spirally impressed lines. 



"Prostate elongate-pyriform; penis from three-fourths to four- 

 fifths the length of penis-sac, very thick; lateral teeth bicuspid." 



Type: L. palitstris Aliiller, fig. 16. Radula, fig. 18. 



Fig. 18 



Section POLYRHYTIS Meek, 1876. 



Shell longitudinally costate. Soft anatomy unknown. 

 Type : L. kingii Meek. 

 Example : L. utaJiciisis Call, fig. 19. 



Family PLANORBID/E. 

 Key to the subfamilies of Planorbidcc. 



Fig. 17 



Shell discoidal 

 Shell spiral . . 



Fig. 19 



. . Planorbince. 

 PompholigincB. 



