86 R. ETHERIDGE ON MOLLUSCA FROM 
numerous small denticulations along its vertical edge; columellar 
side of body-whorl covered by a glossy expanded fold, nearly equal- 
ling in size or expansion the aperture-opening; outer surface of 
shell glossy, and covered with wavy, subangular, or zigzag lines, all 
emanating from the apex of the shell and ranging vertically down 
the expanded body-whorl. 
Loc. Canama. 
OposTOMIA, Sp. 
Three specimens of this genus occur. They are not in a condi- 
tion to be named specifically. 
Loc, Canama. 
Hypropia pusia, Hther. (? Panupmsrrina). (Pl. VII. fig. 11.) 
We have forms of this genus, or one strongly resembling it; 
they do not appear to have been noticed by Gabb or Conrad. 
Whorls five, smooth, rounded; outer lip thin, the inner slightly 
reflected over the umbilicus; body-whorl large; sutural constric- 
tions deep. I can hardly detect any difference between this and 
our Hydrobia pupa, and, as may be expected, many issow may be 
mistaken for it also. ‘There are only two specimens, not well pre- 
served, and I name them with much doubt. 
Loc, Canama. 
[sma ?, Conrad. 
Iscea, sp., allied to I. Ortont, Gabb. 
Mesalia, sp., Amer. Journ. Conch. vol. iv. p. 198. 
Iscea, Conrad, Amer. Journ. Conch. vol. vi. p. 193, t. 10. f. 10-13 
(1870-71). 
Two small shells seem to me to belong to the above species. 
Mr. Gabb’s specimens were too imperfect to show some characters ; 
ours are little better, and fail to show the mouth. 
Loc. Canama. 
Dyris, Conrad. 
D. gracilis, Amer. Journ. Conch. vol. vi. p. 195, t. 10. f. 8. 
Conrad figures and describes a slender shell, to which I refer our 
four specimens. ‘The figure is of little value; but the short descrip- 
tion agrees with our forms. 
Loc. Canama. 
AsstmtnzA, Leach. 
A. crassa, Ether. 
Shell thick, composed of five ventricose whorls; sutures deep ; 
body-whorl large, somewhat subangular in outline; inner or colu- 
mellar lip thick and reflexed over the columella. 
The shell-structure in these Assiminee is thicker than usual, 
