FAMILY LYMN^EID^E 75 



JJmnaa (Umnophysa) senegalensis BECK, Index, p. in, 1838 (nude name), 



fide MORCH, op. cit. t p. 35, footnote. 

 Limncea gronlandica (BECK, MS.) JAY, Cat. Coll., 1850, p. 269, No. 6298. 



MORCH, op. tit., p. 33. 



Limncea molleri BECK, Naturf. Vers. Kiel, p. 123, No. 4, nude name. GERST- 

 FELDT, Land and Sussw. Conch. Sibiriens, p. 37, 1859. 



Lymnaa pingelii (BECK) MOLLER, Index Moll. GronL.p. 5, 1842. MORCH, 

 Am. Journ. Conch., iv, o. 35, 1868, et vars. nitida et solidula et malleata 

 Morch, /. c. 



Lymnaa ivormskioldi BECK, Naturf. Vers., Kiel, p. 123, No. 7, nude name. 



MORCH, Am. Journ. Conch., iv, p. 35, pi. iv, fig. 6, 1868. 

 Limnaa vahlii var. leucostoma MORCH, Prod. Moll. Gronl., p. 4, No. II /? ; 



also var. minor MORCH, Am. Journ. Conch., iv, p. 34, 1868. 

 Limnaa -vahlii var. elongata MOLLER (MS.), in Morch, Am. Journ. Conch., 



iv, p. 40, pi. iv, fig. i, 1868. 

 Limncea arctica LEA, Journ. Acad. Nat Sci. Phila., vi, p. 160, pi. xxiv, fig. 



75, 1866. Hudson Bay. 



Range. Greenland to Alaska and south to Minnesota and British 

 Columbia. 



Ft. Resolution ! and Ft. Rae, Great Slave Lake ! Moose River, at 

 Moose Factory, Hudson Bay ! Greenland (many localities) ! Ungava, 

 Labrador ! Weatoga, Canada ! Minnesota (Lapham) ! Stewart and 



FIG. 54. Lymncea vahlii Moller. FIG. 55. Lymnaea vahlii var. pingelii 



(Typical.) Moller. 



Dall Rivers, north of the Yukon, Alaska ! St. Michaels, Norton 

 Sound, Alaska ! headwaters of the Yukon in Lakes Bennett, Marsh, 

 and Lindeman ! Loring, Southeastern Alaska, on Behm Canal ! 

 Shawnigan Lake, British Columbia ! Headwaters of the Liard 

 River in Lakes Finlayson and Frances ! Hannah Bay near Moose 

 Factory ! 



Making the usual allowances for variation, this is a fairly well dis- 

 criminated species, which frequently has been identified as Z.. desidi- 

 osa, palustris, etc. The largest are more fragile, smaller and paler 

 than L. palustris, and not especially similar to it. I have had the 

 advantage of being able to consult a very large series of authentically 

 named Greenland shells, received from Morch and others, as well as 

 the fine Arctic series in the National Museum. Most of the specimens 

 are microscopically wrinkled on the surface, like L. palustris, but 

 this character is not absolutely constant. 



