GUDE & woodward: on helicella, ferussac. 177 



Genus Vitrea, Fitzinger, 1833. 



Type, Helix diaphana (Studer), Fitzinger. 



1821. Helicella [para] : Ferussac, Tabl. syst. Lima§ons, Jan. ed., p. 41 



(June ed., p. 37). 

 1833. Discus [pars] : Fitzinger, Beitr. Landesk. Oesterr., iii, p. 99. 

 1833. Vitrea: ib. 

 1837. Hyalinia, Ag. (Msc.) [pars] : Charpentier, Neue Denkschr. Allg. 



Schweiz. Gesell., i [No. 2], p. 13. 



1837. Polita [pars] : Held, Isis, xxx, hft. 12, col. 916. 



1855 ) 



^ ' \ Crystallus : Lowe, Proc. Zool. Soc. Lond., 1854, xxii, p. 178. 



1855 1 



jj ,'!- Aplostoma [pars] : Moquin-Tandon, Hist. Moll. France, ii, p. 72. 



Genus Helicella, Ferussac, 1821. 



Type, Helix cellaria, Mliller ' (selected by Gray in 1847). 

 1815. Vortex [pars] : Oken, Lehrb. Naturg., iii, abth. 1, p. 314. {Non 



Humphrey, 1797.] 

 1821. Helicella [pars] : Ferussac, Tabl. syst. Limagons, Jan. ed., p. 41 (June 



ed., p. 37). 

 1833. Oxychilus [pars] : Fitzinger, Beitr. Landesk. Oesterr., iii, p. 100. 



[Non Oxycheila, Dejean, 1825 (Coleopt.).] 

 1837. Hyalinia, Ag. (Msc.) [pars] : Charpentier, Neue Denkschr. Allg. 



Schweiz. Gesell., i [No. 2], p. 13. 

 1837. Polita [pars] : Held, Isis, xxx, hft. 12, col. 916. 

 1850. Hyalina [pars] : Albers, Heliceen, p. 66. [Non Schumacher, 1817 



(Marginellidse), 7iec Studer, 1820 (Vitrina).] 



-^ ' y Lucilla : Lowe, Proc. Zool. Soc. Lond., 1854, xxii, p. 177. 



Q "i'K Aplostoma [pars] : Moquin-Tandon, Hist. Moll. France, ii, p. 72. 



Subgenus helicella, s.s 



1857. Euhyalina : Albers, Malak. Blatt., iv, p. 91. 



1907. Euhyalinia : Taylor, Monpg. Moll. Brifc. Is. [ii], p. 18. 



Subgenus retinella (Shuttleworth MS.), Fischer, 1877. 



Type, Helix olivetorum, Gmelin (indicated by Fischer).® 



1877. Retinella (Shuttleworth MS.) : Fischer, Notitise, Malac. Shuttle- 



worth, ii, p. 5. 



1878. JSgopina^ : Kobelt, in Rossmassler's Icon., vi, p. 15. 



Genus Petasina, Beck, 1847.'^ 



Type, Helix fulva, Miiller (selected by Gray in 1847 ^). " 

 1833. Conulus [pars] : Fitzinger, Beitr. Landesk. Oesterr., iii p. 94. [Non 

 Leske, 1778 (Echinod.).] 



1837. Petasia [pars] : Beck, Index Moll., p. 21. [Non Stephens, 1828 



(Lepidopt.) ; nee Morren, 1829 (Infusor.) ; nee Audinet-Serville, 

 1831 (Orthopt.).] 



1838. Cernuella [pars] : Schliiter, Kurz. syst. Verzeichn., p. 6. 



1847. Petasina : Beck, Amtl. Ber. 24 Versamm. Deutsch. Naturf., p. 122. 



** The well-known British species, nitidula, Drap., pura, Alder, and radiatula, 

 Alder, are now placed in this subgenus on anatomical grounds. 



' Previously the species of this subgenus had been referred to Mesomphix, 

 Rafinesque (Journ. de Physique, Ixxxviii, 1819, p. 425), but that name is now 

 reserved for American species only. 



VOL. XIV. — OCTOBER, 1921. 13 



