HELICINIDA. 245 
2. HELICINA DEPRESSA. B. M. 
Shell depressed, thin, very minutely decussated, under a lens, 
with rather oblique and concentric striz, pellucid, pale horn- 
coloured; spire scarcely raised, slightly mucronate; whorls 5, 
almost flat, enlarging rapidly, last depressed, grooved above 
behind the aperture; aperture oblique, triangular; columella 
very short, sending forth an arcuated, impressed line, which 
surrounds the thin basal callus; peristome expanded, slightly 
reflexed; upper margin depressed, furnished with a middle- 
sized tooth on the middle of its inner side; basal margin rather 
straight, with a single tooth near the columella. Height 35, 
greatest breadth 7, least br. 6 mill. 
Helicina depressa, Gray, in Zool. Journ. i. p. 69, t. 6, f. 14; Désh. 
in Lam. Hist. viii. p. 164, n. 18; Sow. Thes. n. 4, p. 3, t. 1, £.47; 
Pfr. Ic. n. 2, p. 12, t. 7, £14, 15; Pneum. Mon. p. 340. 
B. Spire a little more raised, teeth of the aperture less distinct 
(hype ie.t. 7, £12, 13), 
Helicina Leana, Adams, in Proc. Bost. Soc. 1845, p. 11. 
Hab. Jamaica. 
3. HELICINA PLICATULA. 
Shell depressed-conoidal, rather solid, very elegantly and regularly 
sculptured with oblique folds, shining, horn-coloured; spire 
short, conoidal, rather pointed; whorls nearly 5, moderately 
convex, the last one impressed above, angulated very indis- 
tinctly on the periphery; aperture oblique, lunate; columella 
very short, simple, diffused into a very thin callus; peristome 
rather thickened, flesh-coloured, with the upper margin sinuous; 
basal margin slightly toothed near the columella, Height 3, 
greatest breadth 5, least br. 4 mill. 
Helicina plicatula, Pfr. in Proc. Z. S. 1848, p. 123; Je. n. 3, p. 13, 
t. 8, f. 36-39; Pneum. Mon. p. 340. 
ee striatula, Rang. in Mus, Cuming ; not Sowerby, nor Pot. 
Mich. 
Hab. Martinique. 
4, HELICINA RUGOSA. B. M. 
Shell depressed, rather thin, very elegantly sculptured with 
crowded oblique plaits, pellucid, shining, reddish-amber-co- 
loured ; spire short, conoidal; whorls 5, moderately convex, in- 
creasing regularly, the last one impressed on the middle of its 
lower side; aperture oblique, entire, semiovate; columella 
simple, very short; peristome whitish, spreading narrowly, 
Y 2 
