82 LAND AND FRESH WATER MOLLUSKS 



Adula H. ADAMS, P. Z. S., 1861, p. 145 ; P. multivolvis Case, not Adula 



H. and A. Adams, 1857. 

 Ancceus H. ADAMS, P. Z. S., 1869, p. 275 ; not Ancceus Fauvel, 1863. 



Subgenus Tropidiscus Stein. 



Tropidiscus STEIN, Schn. u. Muscheln Berlins, p. 76, 1850; P. complanatus 



Stein ( = marginatus Drap. + umbilicatus Miiller). 

 Trophidiscus H. and A. ADAMS, Gen. Rec. Moll., 11, p. 263, 1855, in 



synonymy. 

 Anisus FITZINGER, Verz, p. in, 1833, ex parte, not of Studer, 1820, nor 



Dujardin, 1821. 

 Gyrorbis MOQUIN TANDON, Hist. Moll. Terr, et Fluv. de France, pp. 423, 428. 



1885 (not of Fitzinger, 1833); P. carinatus Miiller; Gray's Turton, 



new ed., p. 237, 1857. 

 Tropodiscus SURBECK, Moll. Faun. Vierwaldstattensis, Rev. Suisse de Zool., 



vi, p. 435, l8 99- 



> Tropidiscus WESTERLUND, Act. Soc. Fauna Fennica, xin, p. 113, 1897, ist 



sp. P. umbilicatus Miiller. 



> Diplodiscus WESTERLUND, op. cit., p. 115, 1897, ist sp. P. vortex Linne. 



Section PARASPIRA Dall,* nov. 



Spirorbis SWAINSON, Malac., p. 337, 1840; P. rotundatus Poiret ( + P. 



vulgaris Swains.), not Spirorbis Daudin, Vermes, 1800. 

 Gyrorbis MORCH, Vidensk. Meddel. Kjbb., for 1863, p. 313, 1864, not of 



Fitzinger, 1833. 



Planorbis (sp.) AGASSIZ, in Charpentier, Fauna Helv., p. 21, 1837. 

 Anisus (sp.) FITZINGER, Verz, p. in, 1833 ; not of Studer, 1820. 



Subgenus Hippetitis Agassiz. 



Hippeutis AGASSIZ, in Charpentier, Fauna Helv., p. 22, 1837 ; P. complanatus 

 Drap. (= P. fontanus Lightfoot). HARTMANN, Syst. Uebers., table, 

 1840 ; Erd. u. Sussw. Cast., pp. 51, 87, 1844. GRAY, in Turton' s Man., 

 ed. ii, p. 243, 1857. MORCH, Vidensk. Meddel., 1863, p. 316, 1864. 



Hippeutes MRS. GRAY, Figs. Moll. An., iv., p. 119, 1859. 



Section MENETUS H. and A. Adams. 



Menetus H. and A. ADAMS, Gen. Rec. Moll., n, p. 262, 1855 ; no type 

 selected (not of Chenu, 1869, or Fischer, 1883). BINNEY, Land and 

 Fw. Sh. N. Am., 11, p. 125, 1865. 



Menetus DALL, Ann. Lye. N. Hist. N. Y., ix, p. 351, 1870; P. opercularis 

 Gould. CLESSIN, Conch. Cab., ed. 11, xvn, p. 33, 1886. WESTER- 

 LUND, Act. Acad. Sci. Slav. Merid., Zagrabiae, CLI, p. 120, 1902, P. 

 boissyi Pot. et Mich. 



Heterodiscus WESTERLUND, op. cit., 1902, not of Sharp, 1886, Insecta. P. 

 libanicus Westerlund. 



Section DREPANOTREMA Crosse and Fischer. 



Drepanotrema C. and F. , Miss. Sci. Mexique, n, pp. 59, 75, pi. xxxill, fig. 

 2, 1880; P. yzabalensis C. & F. ; Fischer, Man., p. 509, 1883. 



