i8o Bryant Walker 



Genus PARAPTERA Ortmann, 191 1. 



The type of this genus is U . gracilis Bar. If, as claimed by Frierson and 

 others, this is the Unio fragilis Raf., which the latter in 1831 made the type 

 of his genus Lasmonos, this name would have priority over Paraptera. 



Frierson (42, p. 6) has suggested that if Icptodon Raf. should prove to 

 belong to this genus, Lcptodca Raf., of which Icptodon is the type, would 

 have to be used. 



Genus OBOVARIA Rafinesque, 1819. 



OnovARiA ciKCULus (Lea). 



Ohliquaria subrotiinda Raf. has been identified as this species by Say 

 and Conrad and the latter adds Obovaria striata Raf. as a synonym. The 

 specimens imder both of these names in the Poulson collection, according 

 to A^anatta (140, p. 552), are this species. If identifiable from the original 

 descriptions, either of Rafinesque's names would have priority. 



OnovARiA Ki.LiPSis (Lea). 



Conrad has identified Amhlcma olivaria Raf. as this species and accord- 

 ing to Vanatta (140, p. 553) so also is the shell in the Poulson collection 

 under that name. If identifiable from the original description Rafinesque's 

 name has priority. 



OnovARiA i.ENS (Lea). 



According to Ortmann (79, p. 323) this species is not specifically dis- 

 tinct from O. circuhis (Lea). Vanatta (140, p. 552) states that the shell 

 labelled Unio Icvigata Raf. in the Poulson collection is this species. If iden- 

 tifiable from the original description, Icvigata would have precedence 



OnovARiA RKTUSA (Lam.). 



According to A^anatta (140, p. 552) this is the Obovaria torsa Raf. of the 

 Poulson collection. 



Genus CARUNCULINA Simpson, 1898. 



Tliis group is clearly entitled to generic rank as stated by Ortmann (81, 

 p. 68), who has shown that the type is Unio parvus P.ar. and not tc.vascnsis 

 Lea. 



Frierson ( .]2. p. 7) has identified C. glaiis (Lea) as the Iniio (To.ro- 

 lasnia) li-ridiis Raf. and consequently substitutes Toxolasnia Raf. for Cor- 

 nnciilina Simp. 



Genus LAAIPSILIS Rafinesque, 1820. 



Laatpsilis alata (Say). 



Wanatta (140, p. 552) states that the shell labelled Mctapicra incgc. Intern 

 Raf. in the Poulson collection is this species. Alata is the tvpe of Froftcra 

 Raf. 



