THE NATURAL HISTORY SURVEY. 335 
Length, 4.00; width, 2.00; aperture length, 1.50; width, 1.10 mill. (10497.) 
Animal and Radula: Similar to A. lmosa. 
Distribution: New York to Illinois and Minnesota. (Pils- 
bry.) 
Geological distribution: Pleistocene. 
Flabitat: Same as A. limosa. 
Remarks: This species is distinguished from all others of 
the genus by its narrow, elongated whorls and rather acute 
spire. It is said by Mr. Pilsbry to be the narrowest of the 
genus. JLwustrica does not seem to be at all common and has 
only been found at Berry Lake and Joliet. , 
SuspcEnus CINCINNATIA, Pilsbry, 1891. 
Proc. Phil. Acad., p. 327, 1891, 
Radula more minute and denticulations finer than in the 
typical form. 
136. Amnicola cincinnatiensis Lea, pl. xxvi, fig. 14. 
Cyclostoma cincinnatiensis LEA, Proc. Amer. Phil. Soc., I, p. 289, 1840; 
Trans. Amer. Phil. Soc., VIII, p. 229, pl. vi, fig. 62, 1843. 
Amnicola sayana ANTHONY, in HALDEMAN, Mon., p. 19, pl. i, fig. 4, 
1844? (Figs.4 and 11 are misnamed in Haldeman; 4 is the present 
species and 11 is Pomatiopsis cincinnatiensis Anthony.) 
Shell: Of good size, swollen, umbilicated, rather solid; 
color ranging from greenish to yellowish-brown, translucent; 
surface smooth and shining, lines of growth well developed, 
crowded; sutures forming deep channels between the whorls; 
apex small, rounded, smooth, brownish; spire broadly conic, ele- 
vated; whorls five to six, rapidly increasing, swollen, rounded, 
the last somewhat loosely coiled so that the aperture is continu- 
ous and separated from the body-whorl; aperture roundly ovate, 
bluish-white within; peristome continuous, simple, thin, sharp, 
appressed to the body-whorl only at the upper ‘part; base 
rounded, with a small, rounded umbilicus of great depth. 
Length, 5.00; width, 4.00; aperture length, 2.00; width, 1.75 mill. (10653.) 
ww Dio ewes * 4.00; A “s CAN) aaa AG a (10653.) 
Animal: Yellowish-white above, whiter on base of foot; 
subtransparent; foot short and wide, auriculated before, rounded 
behind and constricted in the center; operculigerous lobe and 
operculum as in /mosa,; rostrum short; tentacles long and slen- 
der, blunt; eyes, mantle and verge as in /mosa. 
Radula formula: $s3-+?¢sthtslatttestrs (3 — 1 — 3); 
(Mus. No. 12769); central tooth similar to that of “mosa, but ends 
