LYMNZZIDA 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 
whorl, 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 proxima. 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, clodes, palustris and um- 
brosa, from all of which it is quite distinct. 
Lea’s types of provima 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 XX XVIII (ex. coll. Walker). For the sake of com- 
parison, Sowerby’s descriptions are appended : 
“Limnea 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.” 
“Limnea 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., pl. 
!7, 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 pro.vima also inhabits this lake as well as its variety 
rowellit. 
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. 
