7 LAND AND FRESH WATER MOLLUSKS 



Hudson Bay ! Fort Resolution, Great Slave Lake ! Winisk, Kawino- 

 gans, and Attawapiskat Rivers, S. E. Keewatin ! (Mclnnes). 



FIG. 59. Lymncza catascopium Say, var. FIG. 60. Lymncea catascopium Say 

 sumassilBd. (British Columbia). (Delaware). 



Var. sumassi: Snake River, Idaho ! Lake Washington, Seattle ! 

 Sumas Prairie, British Columbia. 



Quite variable and frequently confounded with L. adelince, L. buli- 

 moides, L. solida, etc. The Pacific Coast form is quite close to the 

 typical form of the species, but is thinner, less uniform, and some- 

 times larger. Binney's figure 57 is made from a specimen probably 

 of a rather swollen variety of palustris. 



*Lymnaea (Stagnicola) adelinae Tryon. 



Limncsa adelince TRYON, Mon. Limn., p. 82 (108), pi. xvm, fig. 6, 1872 

 (San Francisco, Calif.). 



Range. California to Vancouver Island, B. C. 



A small species, recalling L. bulimoides rather than catascopium, 

 and perhaps identical with Lea's original bulimoides, 

 as indicated by his types, but not with L. techella 

 Haldeman, which is very generally labelled buli- 

 moides. 



FIG. 61. Lym- Lymnaea (Stagnicola?) perpolita n. sp. Plate n, 



ncea adelince. r- so 



figs. 6, O. 



Shell small, translucent, dark amber color, with a darker line at 

 resting stages ; smooth, except for fine lines of growth, brilliantly 

 polished ; whorls four, tumid, rapidly increasing, separated by a pro- 

 nounced suture ; spire short, rather obtuse ; aperture ovate, longer 

 than the spire, with a very thin wash of callus on the spire, the pillar 

 lip slightly reflected, with a small perforate umbilicus behind it ; pillar 

 straight, with no twist or fold, outer lip thin, sharp. Length of 

 shell 1 1 ; of aperture 7 ; breadth of shell 8.5 ; of aperture 4.5 mm. 



Range. Nushagak, Bristol Bay, Alaska. 



This shell is so elegantly polished that it may be an Amphipeplea. 

 It has the rich dark amber color of some Succineas. I have seen but 



