274 THE CHICAGO ACADEMY OF SCIENCES. 
Amer. Phil. Soc., IX, p. 9, 1844; Obs., IV, p. 9, 1848; Expl. in Neb., II, pt. 3, 
p. 724, 1859 
Lymnea philadelphica WuHeEaATLEY, Cat. Sh. U. S., p. 24, 1843—Scunpper, 
Bull. Nat. Mus., 23, pp. 33, 43, 201, 1885. 
Limnea philadelphica Hatp.,, Mon. Limn., p. 33, pl. X, fig. 10, 1842.— 
Antuony, L. & F.-W. Sh. Cin., 1848. 
Limnea philadelphica Binney, Land & F. W. Sh. N. A., II, p. 50, fig. 71, 
1865—Tryon, Amer. Journ. Conch., III, p. 196, 1867—Sows., Conch. Icon., 
RVI Sp. 82; pl 12, fic. 82) 1872: 
Lymnea galbana var. philadelphica Dati, Alaska Moll. p. 74, fig. 52, 1905. 
Lymnea desidiosa var. philadelphica Jay, Cat., p. 269, 1852. 
Lymnea acuta LEA, Trans. Amer. Phil. Soc., V, p. 114, pl. 19, fig. 81, 1837; IX, 
p. 12, 1841; Obs., I, p. 226, 1837—Lea, Proc. Phil. Acad., 1860, p. 147. 
Lymnea acuta WHEATLEY, Cat. Sh. U. S., p. 23, 1845.—Scunpper, Bull. Nat. 
Mus., 23, pp. 14, 200, 1885. 
Limnea acuta Harp., Mon. Limn., p: 33, pl. 10, fig. 14, 1842—ANTHONY, 
L. & F.-W. Sh. Cin., 1848. 
Limnea acuta Bett, Geol. Surv. Canada, Rep. Prog., p. 252, 1859.—BInnEy, 
Land & F.-W. Sh. N. A., II, p. 5, fig. 70, 1865—Tryon, Amer. Journ. Conch., 
III, p. 196, 1867. 
Lymnea desidiosa var. acuta JAy, Cat., p. 269, 1852. 
Limnea pallida (not of Adams) Cpr., Rep. Brit. Asso., pp. 209, 213, 1856.— 
WuiteAVves, Can. Nat. & Geol., VI, p. 458, 1861.—Cpr., Can. Nat. & Geol., VI, 
p. 458, 1861; Smith. Mis. Coll. pp. 120, 160, 1872—-CaLkins, Proc. Ottawa 
Acad. Sci., p. 25, 1874; Cin. Quart. Journ. Sci., I, p. 323, 1874.—?Dawson, Brit- 
ish N. A., Bound Com., p. 349, 1875.—WaAttTon, Proc. Roch. Acad. Sci., II, p. 12, 
pl. 6, figs. 12, 13, 1891—Currier, Kent. Sci» Inst. Mis. Pub., No. 1, 1868.— 
WALKER, Journ. Conch., II, p. 330, 1879-—SuHiMEk, Bull. Lab. N. H., Univ. Iowa, 
I, p. 68, 1888—WALKER, Nautilus, VI, p. 34, 1892; Rev. Moll. Mich. p. 17, 
1894—Wa ton, The Museum, IV, p. 133, 1894—Baxer, Trans. Acad. Sci. St. 
Louis, VIII, p. 89, 1898—Huett, Nat. Hist. La Salle Co., p. 104, 1898 —LeEtTson, 
Bull. N. Y. State Mus., LXXXVIII, p. 55, 1905 (part). 
Lymnea pallida LEA, Proc. Phil. Acad., p. 81, 1856—Currier, Sh. Grand 
River, Mich., 1859——Baker, Bull. Ill. State Lab., VII, p. 105, 1906. 
Limnea pallida Letson, Bull. Buf. Soc. Nat. Sci., IX, p. 242, 1909. 
Limnea pallida Mires, Geol. Surv., Mich., 1860, p. 237, 1861. 
Limnophysa pallida DECAmp, Kent. Sci. Inst., Mis. Pub., No. 5, p. 8, 1881.— 
Keyes, Bull. Essex Inst., XX, p. 71, 1888. 
?Limnea truncatula Woopwarp, Man., p. 399. 
SHELL: Subconic, pointed, oblong, rather thin, frequently some- 
what inflated; periostracum generally light yellowish horn color; sur- 
face shining, covered with numerous coarse lines of growth; under 
a strong lens very fine spiral lines may be seen; whorls 514, rounded, 
somewhat shouldered, the shoulder being near the suture; the last 
whorl is very large, half the length of the entire shell, generally com- 
pressed but quite obese in some specimens ; spire acute, sharply-conical ; 
nuclear whorls 114, resembling those of Galba parva in outline and 
