Doubtful and Spurious Species. 



Planorhis ohtusa, Wheat). 

 Planorhis spirorbis, Shep- 



pard. 

 Planorhis alba, Sheppard. 



Planorbis parallehis, Say. 

 Planorhis niger, De K. 

 Planorbis complanatus, 



Rav 



Fossil Species, 



Planorbis spectabilis, Meek. 

 Planorhis utahensis, Meek.- 

 Planorhis vitrinus, Meek & 



Ilayden. 

 Planorbis nehras'censis, 



Evans. & Slium. 

 Planorbis vetulus, Meek & 



Ilayden. 



Planorhis convolutus, Meek 

 & Ilayden. 



Planorbis "Planoconvex (P. 

 fragilis), Meek & Hay- 

 den. 



Planorhis subumhilicata, 

 ( Valvata), Meek & Hay- 

 den. 



Genus Alicylus. 



*Ancylus calcarius, De K. 

 *Ancylus haldemani, Bourg. 

 Anci/lus depressus, Hald., not 



Desk. 



Ancylus diaphanus, Hald., De K. 



*Ancylus elatior, Anth. 



Ancylus filosus, Conr., Hald., De 

 A'., Midi. 



Ancylus fuscus, C. B. Ad., Hald., 

 GUI., DeK. 



* Ancylus o bscur us, iZaW. 



Ancylus parallelus, Hald., C. B. 

 Ad., DeK. 

 Ancijlus rivularis, Gld., not Say. 



Ancylus rivularis, Sai/, Hald., De 

 K.f M. E. Gra)j, not of Gld. 



Ancylus tardus, Say, Hald., C.B. 

 Ad., De K. 



*Ancylus ne-wberryi, Lea. 

 *Ancylus crassus, Hald. 

 Ancylus caurinus, Cooper. 

 Ancylus patelloides, Lea. 



Doubtful Species. 

 Ancylus drouetianus, Bourg. 



Genus Velletia. 

 *Velletia nuttallii, Hald., DeKay. 



Fossil Species. 

 Ancylus (^Acroloxus) minutus, Meek & Ilayden. 



