140 
THE CHICAGO ACADEMY OF SCIENCES. 
SHIMEK, Bull. Lab. Nat. Hist. State Univ. Iowa, I, p. 67, 1888.— 
Keyes, Bull. Essex Inst., XX, p. 70, 1888.—GrantT, An. Rep. Geol. 
& Nat. Hist. Surv. Minn., XVI, p. 483, 1888.—Ho.zincer, An. Rep. 
Geol. & Nat. Hist. Surv. Minn., XVI, p. 490, 1888—CxLL., Journ. 
Conch., VI, p. 64, 1889.—GrLBeRT, Mon. U. S. Geol. Surv., I, pp. 
210, 298, 1890—SHIMEK, Bull. Lab. Nat. Hist. Univ. Iowa, I, p. 67, 
1890.—Pirspry, Proc. Phil. Acad., pl. XVII, fig. 2, 1890.—CoopeEr, 
Proc. Cal. Acad. Sci., ii, III, p. 70, 1890.—Ottawa Nat., IV, p. 55, 
1890—STEARNS, Proc. Nat. Mus., XIV, p. 100, 1891—WALToN, 
Proc. Roch. Acad. Sci, II, p. 11, pl. 6, fig. 9, 1891—DLatTcHForD, 
Ottawa Nat., VI, p. 118, 1892—Taytor, Ottawa Nat., VI, p. 35, 
1892.—Watker, Nautilus, VI, p. 31, pl. 1, fig. 6, 1892—MARSHALL, 
An. Rep. N. Y. State Mus., XLVII, p. 63, 1893——LartrcHFrorp, Ottawa 
Nat. VII, p. 115, 1893—-WaALkeErR, Nautilus, VII, p. 128, 1894.— 
MarsHALL, Report Exhib. N. Y. World’s Fair, p. 511, 1894— 
BAKER, Science, n. s., II, p. 179, 1895—Watker, Rev. Moll. Fauna 
Mich., p. 17, 1895—Taytor, Ottawa Nat., IX, p. 174, 1895.—Sar- 
GENT, Nautilus, IX, p. 127, 1896-——Snyper, The Museum, III, p. 12, 
1896.—BaKER, Journ. Cin. Soc. N. H., XIX, p. 84, 1897; The 
Museum, III, p. 155, 1897—Wyswa tt, Nat. Sci. Journal, 1, No. 2, p. 
47, 1897.—Baker, Journ. Cin. Soc. N. H., XIX, p. 78, 1897—AML., 
Ottawa Nat., XI, p. 26, 1897.—BakeEr, Chicago Moll. p. 23, 1898; 
Trans. Acad. Sci. St. Louis, VIII, p. 88, 1898—Watton, The 
Museum, IV, p. 132, 1898—Watker, Nautilus, XI, p. 122, 1898— 
HanuaMm, Nautilus, XIII, p. 5, 1899—MutTcHELL, Nautilus, XIII, 
p. 88, 1899—Pirssry, Nautilus, XIII, p. 64, 1899-—Osporn, Pop. 
Sci XXXIII, p. 3, 1899—WatkeEr, Nautilus, XIII, p. 35, 1899.— 
Leverett, Mon. U. S. Geol. Surv., XX XVIII, p. 174, 1899.—BakeEr, 
Nautilus, XIV, p. 69, 1900.—WaALKER & Lane, Geol. Sury. Mich., 
VIL., pt. ii, p. 251, 1900.—BLatcHLEY & ASHLEY, Rep. Geol. & Nat. 
Res. Ind., XXV, p. 248, 1901—Baxker, Trans. Acad. Sci. St. Louis, 
XI, p. 21, fig. 12, pl. 1, fig. 15, 1901—STEARNS, Science, XV, p. 153, 
1902.— WHITEAVES, Ottawa Nat., XVI, p. 91, 1902—Etrop, Bull. 
Univ. Mont., Biol. Ser., No. 3, pp. 112, 160, 1902—CKLL., Nautilus, 
XVI, p. 96, 1903—Watker, Geol. Surv. Mich., VIII, pt. iti, p. 101, 
1903—Baker, Shells of Land & Water, p. 11, fig., pl. fig. 18, 1903. 
—Kerep, West. Amer. Shells, pp. 148, 313, fig. 127, 1904—LeEtson, 
Bull. N. Y. State Mus., LXX XVIII, p. 51, 1905-—-WuitTEAvEs, Ottawa 
Nat., XIX, pp. 31, 32, 1905.—Letson, Bull. Buf. Soc. Nat. Sci., IX, 
p. 242, 1909. 
Limnea stagnalis HALDEMAN, Bost. Journ. Nat. Hist., IV, p. 468, 1844.— 
CarLTon, Proc. Cal. Acad. Sci, i, IV, pp. 51, 57, 1869.—FROEBEL, 
Proc. Lyc. Nat. Hist., I, p. 72, 1870.—INGERSOLL, Bull. U. S. G. & G. 
Sucv., [, 1p. dss) 18v52 Proc Daven Acad Scigulinep. daraelonne 
Limnea lanceata, Ottawa Nat., I, p. 58, 1882; IV, p. 58, 1890. 
Limnea lepida, Ottawa Nat., I, p. 58; IV, p. 56, 1890; VI, p. 33, 1892. 
SHELL: Differing from stagnalis in being more regularly fusi- 
form, having a less angulated and more gracefully rounded body whorl 
and a more pronounced twist of the axis. The spire in typical stagnalis 
