344 THE CHICAGO ACADEMY OF SCIENCES. 
Animal: Similar to that of P. lapidaria. 
Radula: Not examined. 
Distribution: Western New York west to lowa and Min- 
nesota, Northern Michigan south to the Ohio River. 
Geological distribution: Pleistocene. 
Hatitat: Similar to P. lapidaria, but clinging to stones - 
when in the water. 
Remarks: Cincinnatiensis is more common than /apidaria, 
at least in the area under consideration. This species may be 
distinguished from Japidaria by its fewer whorls and more 
robust shell; the spire is also longer and more attenuated in 
lapidaria than in the present species. The male shell is much 
wider than that of the female, the last whorl of the former 
being much enlarged to accommodate the extraordinarily large 
verge. The females have rather long and elongated shells. 
(Compare figures.) This species has been found only at Joliet, 
in the western region. 
142. Pomatiopsis lapidaria Say, pl. xxx, fig. 33; pl. xxxi, fig. 12. 
Cyclostoma lapidaria Say, Journ. Phil. Acad., Vol. I, p. 15, 1817. 
Paludina lustrica SAY, Journ, Phil. Acad., Vol. II, p. 175, 1821. 
Shell: Elongated, turreted; color dark brownish-horn; 
surface shining, lines of growth crowded, slightly wrinkled, 
numerous; apex rounded and depressed, two nuclear whorls 
smooth, polished, horn-colored; spire long-conic, turreted; su- 
tures very much impressed; whorls six, well rounded; aperture 
roundly ovate, dark colored inside; peristome thin, continuous, 
reflected so as to form a rounded rim for the aperture; the last 
whorl, near the aperture, is almost free from the body-whorl; 
base of shell rounded; umbilicus round and deep. 
Length, 7.00; width, 3.50; aperture length, 2.00; width, 1.75 mill. (10226.) 
50; «Ale B00 Pea af BONE to UBO Ce 
Animal; With a short, broad foot, slightly produced at 
the anterior outer corners; rounded behind; foot provided with 
three sinuses, of which one separates the foot into an anterior 
and a posterior part; above this there is a sinus at right angles 
with the first, which separates the foot from the body, the up- 
per fold of which merges into the operculigerous lobe poste- 
riorly; above this there are two folds, one extending from the 
lower base of the rostrum to the base of the tentacle, and the 
other from the former point to and beyond the constricted 
portion called the neck; rostrum rather long, blunt, containing 
