OF NORTH AMERICA. 361 



REMARKS: Proxima resembles certain long-spired forms of pal- 

 ustris, from which it may be distinguished by its more convex body 

 zvhorl, longer and more regularly conic spire and rounder aperture, 

 and more rapidly enlarging whorls. Long-spired palustris from the 

 Mississippi Valley region have usually a more obese body whorl, but 

 the California long-spired palustris have usually a less obese body 

 whorl than proximo,. The difference in the spire whorls, the aperture 

 and the body whorl, is sufficient to distinguish proxima from pal- 

 ustris. It apparently replaces reflexa west of the Rocky Mountains, 

 and has been named by collectors reflexa, elodes, palustris and um- 

 brosa, from all of which it is quite distinct. 



Lea's types of proxima agree with Binney's figure, and show 

 well the rapid enlargement of the whorls which is so characteristic 

 of this species. Tryon's figure in Continuation Haldeman, is not char- 

 acteristic. Sowerby's californica as well as his interstriata are 

 synonyms of proxima. An authentic specimen of californica, which 

 has been compared with Sowerby's type in the British Museum, is 

 figured on plate XXXVIII (ex. coll. Walker). For the sake of com- 

 parison, Sowerby's descriptions are appended : 



"Limncea californica: Shell elongate, pyramidal, thin, semi-pel- 

 lucid, pale horn colored ; spire elevated, whorls five, oblong, moderately 

 convex ; aperture ear-shaped, short ; inner lip single-plaited in the mid- 

 dle ; columellar fold twisted backward." 



"Limncza interstriata: Shell pyramidal, acuminated, solid, yel- 

 lowish chestnut ; distantly slightly longitudinally riged, finely striated, 

 longitudinally striated; spire elevated; whorls four, attenuated, rather 

 convex; aperture subtrigonal, slightly orange; columella, white; 

 columellar fold, thick, broad." 



The angulate specimen figured by Tryon (Con. Hald. Mon., pi. 

 17, fig. 4), as a form of palustris, is probably a pathologic phase of 

 proxima. The strongly angulated whorls make a very peculiar looking 

 shell; Tryon's specimen (No. 58523 Acad. Nat. Sci. Phil.) measures 

 as follows : Length, 22.00 ; width, 9.75 ; aperture length, 10.50 ; width, 

 5.25. It was collected in mountain lake near San Francisco by Mr. 

 Rowell. Typical proxima also inhabits this lake as well as its variety 

 rowellii. 



Proxima has been made a synonym or variety of palustris by many 

 recent authors, but it would seem to be as much entitled to specific 

 rank as almost any of the palustris-reflexa group. It possesses charac- 

 teristic features which sufficiently distinguish it from its congeners. 



