HANNIBAL: CALIFORNIANT FKESnWATER JIOLLUSCA. 1 ,'39 



Genus LvMXiEA, Lamarck. 



Helix (sp.), Litme, 1758 {H. stagnalis, L.) ; Lymnma^ Lamarck, 1799 

 (//. stagnalis, L.) ; Limneus, Draparuaud, 1801 (emended form); 

 Ltjmnus, Montfort, 1810 (emended form) ; Radix, Monttbvt, 1810 

 [IT. aiiricularia, L.); Limncea, Desmarest, 1812 (emended form), 

 11011 Poll, 1795, polynomial; Lymneus, Braird, 1815 (emended 

 form); Lymncens, Cuvier, 1817 (emended form); Lymnula, 

 Ratinesque, 1819 (emended form) ; Auricularia, Fabricius, 182;3 

 (nude name) ; Lymnea, llisso, 1826 (emended form), not Lytnnea, 

 Katinesque, 1815; Limnea, Fleming, 1828 (emended form); 

 iStagnicola, ' Leacli MS.,' Jeffreys, 1830 {S. communis, Leach MS. 

 = B uccinuin palustre , Miill.), in synonymy; Gulnaria, 'Leach ^MS.,' 

 Turton, 1831 {II. auricularia, L.), in synonymy ; LeacJtia, 

 Jeffreys, 1833 {H. stagnalis, L.), not Leachia, Lesueur, 1821, nor 

 llisso, 1829; Limnophysa, 'Fitz'mger, 1833 (B. palustre, Miill.); 

 Bidimnea, Haldeman, 1841 (Z. megasoma. Say); Neritostoma, 

 'Klein,' H, & A. Adams, 1855 (ZT. auricularia, L.); Auricula, 

 'Klein,' H. & A. Adams, 1858 (iT". stagnalis, L.) ; Eulimneus, 

 Sandberger, 1875 {II. stagnalis, L.) ; Polyrhytis. Meek, 1876 

 {Limncea Kinqi, Meek = R. Auricularia, L.) ; Pseudosiiccinea, 

 F. C. Baker, 1908 (Z. columella, Say). 

 Type, Helix stagnalis, Linne. 



Sub-genus Galea (Shrank). 



Buccinum (sp.), Miiller, 1773 {B. truncatulum, Miill.); Galla, 

 Shrank, 1808 (Z. truncatulum, Miill.) ; Lej^tolimnea, Swainson, 

 1840 {Limneus elongatus, Drap. = Buccinum glabrum, Miill.); 

 Leptolimnmis, Sandberger, 1875 (emended form); Fossaria, 

 Westerlund, 1885 (Z. truncatulum, Miill.) ; Simpsonia, F. C. Baker, 

 1911 (Z. humilis. Say = B. truncatulum, Miill.). 

 Type, Buccinum truncatulum, Miiller. 



Sub-genus Lymncea, s.s. Shell of moderate size, averaging 25 mm. 

 in altitude, dextral, whorls normally sub-appressed or moderately 

 inflated, sub-perforate, aperture succiniform or sub-auriculiform, axis 

 simply retlexed in adolescent stage, with a rudimentary, well-deyeloped, 

 or sub-obsolete marginal fold in adult ; habitat aquatic, chiefly in 

 shallower portions of lakes and in sluggish streams, but not entirely 

 confined to such situations. 



Sub-genus Galba. Shell similar to preceding, but small, averaging 

 10 mm. in altitude, umbilicate, whorls usually well inflated, axis 

 simply reflexed in early adolescence, with a gyrate marginal fold in 

 later development {Lymnoia stage), adult with a smooth vertical 

 expansion of the inner lip reflected over the umbilicus ; habitat, the 

 young in aquatic situations, the adults in springs, or more generally 

 in moist places with Succinea, particularly on tangles of algae. 



The Lymnjfias are characteristically of widespread occurrence. 

 Of the species found west of the Bocky Mountains, four, Z. stagnalis, 

 L.palustris, L. auricularia, and Z. {Galba) truncatula, are circumboreal, 

 all of the remainder, except the newly characterized Z. Cooperi. occur 



