THE CHICAGO ACADEMY OF SCIENCES. 
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TENNESSEE: Hickman Co. (Hinkley). 
GEOLOGICAL RANGE: Unknown. 
Ecotocy: In more or less swampy brooks and streams, in situ- 
ations similar to those in which Galba parva is found. 
Remarks: This curious Lymnzid was at first thought to be 
Lea’s exigua, but his description does not cover the present species 
and the figure in Binney is totally unlike it. The type of erigua is 
not in existence, so that no direct comparison is possible. Sterku 
bears a superficial resemblance to owascoensis, but in that species the 
whorls are decidedly and strongly shouldered, causing them to appear 
like boxes of diminishing size set one upon another, the whorls being 
very flat-sided. The inner lip is also very different in sterku. It may 
be distinguished from parva by its larger shell, generally more flat- 
sided whorls and differently shaped aperture, the inner lip being 
broadly reflected, forming a flat, concave expansion; the lower part 
of the aperture in sterkii is broadly effuse and produced, while in parva 
it is very evenly elliptical. This peculiarity of the lower part of the 
aperture, together with the broad, flat, inner lip, will usually distin- 
guish sterkii from related species. The presence of intermediate 
forms suggests that sterkii is a race of parva rather than a distinct 
species. There is considerable variation in the height of the spire 
and in the width of the shell, some individuals being very narrow, 
while others are quite obese, but all agree in the form of the aperture 
and of the inner lip. The figures well illustrate this variation. 
The variety is named in honor of Dr. Victor Sterki, of New 
Philadelphia, Ohio, who collected the type lot. 
Galba owascoensis (Baker). Plate XXIX, figures 23-25. 
Lymnea owascoensis BAKER, Nautilus, XVIII, p. 141, April, 1905. 
Limnea owascoensis HENDERSON, Nautilus, XX, p. 98, 1907. 
Limnea owascoensis Letson, Bull. Buf. Soc. Nat. Sci., IX, p. 242, 1909. 
SHELL: Small, elongate, turreted, rather thin; color light yellow- 
ish horn; surface shining, marked by close-set lines of growth; in 
some specimens there is a tendency to become malleated; nucleus 
small, round, of the same color as the rest of the shell, in form similar 
to that of Galba parva, the first whorl being smaller; whorls six, 
strongly shouldered, rather flat-sided ; spire elongated, sharply conical; 
sutures deeply impressed; aperture roundly ovate, almost continuous, 
about one-third as long as the entire shell; outer lip thin, sharp; inner 
lip reflected over the umbilicus to form a rather wide, flat projection, 
which is almost erect and strongly emargines the umbilical chink; 
the callus on the parietal wall is generally rather thin, but when heavy 
