Fauna of the Morrow Group 
231 
GASTROPODA 
ACMAEID^ 
Genus LEPETOPSIS Whitfield 
Lepetopsis chesterensis Worth en ? 
1884. Lepetopsis chesterensis. Worthen, Bull. 111. State Mus. Nat. Hist., 
No. 2, p. 25. 
Lower Chester limestone: Chester, Illinois. 
18’90. Lepetopsis chesterensis. Worthen, GeoL Surv. 111., vol. 8, p. 140, 
pi. 25, figs. 1-la. 
Chester limestone: Chester, Illinois. 
A single specimen from the Hale formation, although some- 
what imperfect, appears to be referable to this species. In 
ratio of length to breadth, position of apex, and surface mark- 
ings, its characters, so far as known from the material at hand, 
agree perfectly with Worthen's figures and descriptions. The 
portion of the shell which ought to bear the gentle sinus behind 
the apex is, however, missing. 
The dimensions of the specimen, as restored, would be : length, 
14 mm. ; width, 11 mm. ; height, 6 mm. 
Horizon and locality. Hale formation: East Mountain, Fay- 
etteville, Arkansas (Station 137). 
Lepetopsis sp. 
Plate XVI, figures 5, 5a. 
Another gastropod shell, somewhat larger than the foregoing 
one, is also referred to the genus Lepetopsis. The width is 
about two-thirds the length and the aperture is regularly ellipti- 
cal ; the apex is situated nearer to the margin than to the mid- 
length of the shell and the posterior slope is distinctly concave. 
The surface markings are unknown. The dimensions of the 
only specimen at hand are : length, 19.5 mm. ; width, 13 mm. ; 
height, 5.5 mm. 
Horizon and locality. Kessler limestone : East Mountain, 
Fayetteville, Arkansas (Station 209). 
