96 THE CHICAGO ACADEMY OF SCIENCES. 
& Cznoz. Geol., p. 72, 1881—WuitTE, 3rd An. Rep. U. S. Geol. Surv., p. 445, pl. 
29, figs. 22-23, 1882; Bull. U. S. Geol. Surv., no. 128, p. 80, 1895.—ScHUCHERT, 
Bull. U. S. Nat. Mus., 53, i, p. 357, 1905. 
Limnea (Limnophysa) vetusta Meex, U. S. Geol. Surv. 40th Parallel, IV, 
p. 191, pl. 17, fig. 4, 1877-——Marcou, Proc. Nat. Mus., VIII, p. 337, 1885. 
Lymnophysa vetusta WuHitTE, An. Mag. Nat. Hist., ser. 5, VI, p. 249, 1880. 
“SHELL small, elongate-subovate, or subfusiform ; spire moderately 
prominent, conical, scarcely as long as the aperture; volutions five and 
a half to six, compressed-convex ; last one not very ventricose, some- 
times almost subcylindrical; suture well defined, with comparatively 
little obliquity ; surface showing only obscure lines of growth; aperture 
very narrow, subovate; columella with a moderately distinct fold. 
“Length, 0.56 inch; breadth, 0.26 inch” (Meek). 
Type; U.S: Nat. Mus. no. 693. 
Horizon: Bridger formation, Middle Eocene Period. 
Locatity: Ham’s Fork, north of Fort Bridger, Uinta County, 
southwestern Wyoming. 
REMARKS: “Among existing species this may be compared with 
L. decidiosa of Say, some varieties of which it quite nearly resembles. 
Its body volution, however, is less ventricose, and its aperture less 
expanded, than we see in any of the several forms that have been 
supposed to be varieties of that species. It is, perhaps, more nearly 
allied to some of the real or supposed varieties of L. humilis, Say; 
though not exactly agreeing with any of them. It varies much in 
form” (Meek). 
Vetusta belongs in the subgenus Stagnicola. It closely resembles. 
some of the recent species of the palustris-reflexa groups. 
Galba similis (Meek). Plate XVI, figures 14, 15, 18, 19. 
Limnea similis Mrex, Proc. Phil. Acad., p. 314, 1860.—BinneEy, L. & 
F. W. Sh. N. A., II, p. 72, 1865.—Conrapn, Smith. Check List, p. 9, 1866.—MEEK, 
Simpson’s Rep. Great Basin Utah, pp. 367, 373, pl. 5, fig. 2, 1876.—WuirtE, Bull. 
U. S. Geol. & Geog. Surv. Terr., III, p. 611, 1877—Meex, U. S. Geol. Surv. 
40th Parallel, IV, p. 191, pl. 17, fig. 3, 1877-——-Wuitr, Amer. Journ. Sci. & Arts, 
ser, 3, XX, p. 45, 1880.—MILLErR, Journ. Cin. Soc. N. H., III, p. 82, 1880.; Mes. 
& Cznoz. Geol., p. 72, 1881—WuitE, 3rd An. Rep. U. S. Geol. Surv., p. 445, pl. 
29, figs. 20-21, 1882—-Marcou, Proc. Nat. Mus., VIII, p. 337, 1885.—WHITE, 
Bull. U. S. Geol. Surv., no. 128, p. 80, 1895.—ScHucHERT, Bull. U. S. Nat. Mus., 
53, i, p. 356, 1905. 
Limnophysa similis Waite, An. Mag. N. H., Ser. 5, VI, p. 249, 1880. 
“SHELL small, narrow-subovate, approaching subfusiform; spire 
rather prominent, nearly as long as the aperture; volutions five and 
a half to six, convex; suture rather deep and oblique; surface showing 
only fine, obscure lines of growth, scarcely visible without the aid of 

