274 CATALOGUE OF PHANEROPNEUMONA. 
angle of about 90° with the peristome, which is thin and 
narrowly expanded; basal callus extremely thin, diffused. 
Operculum thin, pale horn-coloured. Height 24, greatest 
breadth 3, least br. 22 mill. 
Helicina Antoni, Pfr. in Z. f. I. 1848, p. 88; Jc. n. 55, p. 44, t. 5, 
f. 35-38; Pneum. Mon. p. 377. 
Hab. Honduras (Dyson). 
§ 9. Peristome not toothed, expanded ; shell not keeled, depressed. 
89. HELICINA MAXIMA. 
Shell globose-depressed, rather solid, smooth, whitish ; spire very 
short, scarcely mucronate; whorls 53, rather flat, enlarging 
rapidly, the last one depressed, more convex beneath ; aperture 
nearly perpendicular, large, semiovate ; columella terminating 
in an indistinct knot, dilated backwards into a semicircular 
callus of the same colour; peristome simple, expanded, and 
slightly reflexed. Height 15, greatest breadth 25, least br. 21 
mill. 
Helicina maxima, Sow. in Proc. Z. S. 1842, p.6; Thes. n. 37, 
p.8,t.1,f11; Pfr. Jc. n. 56. p. 44, t. 6, £. 3,4; Prnewm. Mon. 
p. 378. 
Hab. Jamaica. 
90. HEeLIcINA NOBILIS. 
Shell depressed globose-conic, thick and solid ; white beneath and 
at the end of the last whorl, otherwise rufous or dark brownish- 
red; very smooth, the striz of growth being very light ; some- 
times with a few very light spiral strie; apex obtuse; spire 
convex-conic ; whorls nearly 43, subplanulate, with a rather 
deep suture; last whorl much depressed or even sinuate between 
the periphery and suture at its termination; aperture com- 
pressed above, expanded laterally; lip rather thick, moderately 
reflected along the middle only; with a notch like that of 
H. maxima, Sow. Mean divergence 130°; greatest breadth 0.9 ; 
least br. 0.73; height 0.55 inch. (Adams.) 
Helicina nobilis, Adams, in Ann. Lyc. New York, v. un. 2, p: 49 ; 
Contrib. to Conch. u. 8, p. 133? Pfr. Pneum. Mon. p. 378. 
Hab. Jamaica. 
91. HELICINA CITRINA. B. M. 
Shell rather depressed, thin, faintly striated, shining, diaphanous, 
Jemon-yellow; spire short, somewhat conoidal ; whorls 5, rather 
flat, increasing rapidly, the last one more or less depressed and 
