HELICINID A. 267 
Helicina fragilis, Morelet, Test. Noviss. ii. p. 17, n. 122; Pfr. Pneum. 
Mon. p. 368. 
Hab. Peten, Guatemala. 
69. HELICINA ALATA. 
Shell globose-conic, thin, faintly striated, white, covered with a 
deciduous fuscous periostraca; spire conic, rather pointed; 
whorls 54, convex, last rounded, not descending, deeply im- 
pressed beneath near the circumscript columellar callus ; colu- 
mella simple, receding; aperture large, semicircular; peristome 
simple, thin, slightly expanded, with the margin produced into 
a rather broad wing below its insertion. Height 7}, greatest 
breadth 9, least br. scarcely 8 mill. 
Helicina alata, Menke, MSS.; Pfr. in Z. f. M. 1848, p. 87; Lc. 
n. 54, p. 43, t. 5, f. 18-20; Pnewm. Mon. p. 368. 
Helicina pannucea, Morelet, Testac. Noviss. i. p. 21, n. 52. 
Hab. San Lins, province of Peten, Guatemala (Morelet); Mexico ? 
(Menke). 
§ 8. Peristome not toothed, expanded; shell not keeled, rather glo- 
bose; spire as high as the last whorl. 
70. HenicIna SINUOSA. 
Shell globose-conic, solid, minutely striated concentrically, opaque, 
white; spire conic, pointed; suture impressed; whorls 6, flat, 
last slightly keeled, moderately convex beneath; aperture per- 
pendicular, triangular, sinuate; columella short, flattened, ter- 
minating in a tooth-like knot, dilated backwards into a thin 
callus; peristome thickened, expanded; right margin sinuate, 
ascending, forming a channel with a callous knot, which is 
situated on the keel of the penultimate whorl. Height 11, 
greatest breadth 16, least br. 13 mill. 
Helicina sinuosa, Pfr. in Z. f. IW. 1850, p. 191; Je. n. 94, t. 10, 
f. 7,8; Pneum. Mon. p. 369. 
Hab. Mexico. 
71. HexicrinaA LANIERIANA. 
Shell globose-turbinate, thin, sculptured with irregular oblique 
and crowded concentrical striz, scarcely shining, pale yellow; 
spire conic, acutely mucronate; whorls 7, the first ones flat, the 
penultimate one moderately convex, last roundish, with the 
periphery angulated very indistinctly; columella short, recti- 
linear, receding, dilated backwards into a thin callus; aper- 
ture oblique, ovate, rather triangular; peristome simple, thin, 
