LYMN^EIELE OF NORTH AMERICA. 375 



Limnophysa pingellii Tryon, Amer. Journ. Conch., I, p. 254, 1865. 



Limnceus pingellii Kuster, Conch. Cab., p. 27, taf. 5, figs. 11, 12, 1862. 



Lymncea vahlii var. pingelii Dall, Alaska Moll., p. 75, fig. 55, 1905. 



Limncea vahlii var. nitida Morch, Prod., No. 10 a, Atner. Journ. Concb., 

 IV, p. 35, 1868. 



Limncea vahlii var. pingelii, aa solidula Morch, Amer. Journ. Conch., IV, 

 p. 35, 1868. 



Limncea arctica Whiteaves, Nautilus, XIX, p. 3, 1905; Ottawa Naturalist, 

 XIX, p. 65, 1905. 



Limncea palustris Randolph, Nautilus, p. 109, 1899 (part). 



Shell: Thin, cylindrical, ovate; periostracum dark reddish horn 

 or brownish ; sculpture as in vahlii; whorls 5-6, very convex ; sutures 

 deeply impressed ; spire short, as long as, or shorter than, the aperture, 

 the apex obtuse and generally decorticated ; aperture ovate, somewhat 

 dilated in some individuals; inner lip narrow; appressed to the um- 

 bilical region, leaving a small chink ; columellar callus wide, thin, white ; 

 columella with a longitudinal thickening but with scarcely any twist. 

 In some individuals the rest periods may be seen as light yellowish 

 longitudinal streaks ; from 3 to 5 of these streaks may be seen on each 

 shell. 



Length. 



Width. 



Aperture ler 



•gth. 



Width. 







15.00 





8.00 







mill. 



Morch. 



13.75 



7.75 



6.50 





3.50 



a 



St. 



Michaels. 



12.00 



6.00 



6.00 





3.10 



" 





it 



12.50 



7.25 



7.50 





4.00 



u 





(< 



12.50 



7.10 



6.50 





4.00 



a 





cc 



12.75 



6.50 



7.00 





3.25 



it 





" 



10.00 



5.50 



4.50 





5.00 



a 





" 



Type : Location not ascertained. 



Type Locality: Tank on the northern shore of Baal's River, 

 vicinity of Nepiset Sound, Greenland. 



Animal, Jaw, Radula and Genitalia : Not recorded. 



Range: (Figure 42). Western Greenland to western Alaska. 

 A form of the Arctic and Hudsonian divisions of the Boreal life zone. 

 Future research will doubtless connect the two widely separated areas 

 on the map, and the race will probably be found to inhabit the Yu- 

 konian, Mackenzian, Hudsonian and Greenlandian regions. 



RECORDS. 

 Alaska. 



St. Michaels (E. W. Nelson) ; flats near St. Michaels (Randolph) ; Dall 

 River (Dr. I. T. White). 



British America. 



Yukon territory: Stewart River, near Mayo River (J. Keele; Whit- 

 eaves). 



