90 CATALOGUE OF PHANEROPNEUMONA. 
conical and scarcely truncate above; suture deep, simple; 
whorls 7, very convex; the penultimate somewhat flattened on 
the side of the mouth, the last one narrower, cylindrical, not 
compressed round the perforation; aperture circular, scarcely 
produced at its base beyond the axis; peristome continuous, 
much thickened, slightly reflected, shortly affixed to the penult 
whorl, dilated, on the columellar side, imto an ear-shaped ap- 
pendix. Length 28, breadth 125 mill. 
Cyclostoma Mani, Poey, Mem. Hist. Nat. Cuba, i. t.7, f. 19-22 ; 
Pfr. Ic. 0. 387, t. 47, f. 29-31. 
Cyclostoma tortum var., Poey, Mem. ii. p. 105, t. 13, f. 23, 24. 
Megalomastoma Mani, Pfr. Pnewn. Mon. p. 128. 
Hab. Cuba (Poey). 
7. MEGALOMASTOMA VENTRICOSUM. B. M. 
Shell umbilicate, oblong-ovate, subtruncate, thick, smooth, flesh- 
coloured; whorls 5, convex, enlarging rapidly ; the penultimate 
broadest, the last narrower, angulated round the narrow um- 
bilicus; aperture circular, fulvid inside; peristome continuous, 
expanded, thickened, white, shortly affixed to the penult whorl, 
with the upper and columellar margins dilated into slight 
angles. Length 29, breadth 16 mill. 
Cyclostoma ventricosa, Orb. Moll. Cub. i. p. 256, t. 21, £3; Chenu, 
Ill. Conch. t. 1, f. 15. 
Cyclostoma ventricosum, Sow. Thes.n.170, p. 151, t. 28, f. 183, 184; 
Pfr. Ic. n. 112, p. 111, t. 17, f. 20, 21. 
Megalomastoma ventricosum, Pfr. in Z. f. I. 1847, p. 109, n. 10; 
Consp. n. 188; Pneum. Mon. p. 128. 
Farcimen tortum var., Gray, Cat. Cycl. p. 29. 
Hab. Cuba. 
8. MEGALOMASTOMA ALUTACEUM. 
Shell perforate, ovate-oblong, truncate, rather thick, impressedly 
punctate and granularly wrinkled, whitish, with a violaceous 
tinge; whorls 44, convex, the last one lessened, detached and 
deflected anteriorly, angularly compressed near the perforation ; 
aperture rather perpendicular, nearly circular; peristome con- 
tinuous, thickened, and slightly reflected, dilated and subauricu- 
late above and on the left margin. Length 23, breadth 11 mill. 
Cyclostoma alutaceum, Menke, MSS.; Pfr. in Z. f. M. 1846, p. 85; 
Ie. n. 114, p. 113, t. 17, £. 18, 19. 
Megalomastoma alutaceum, Pfr. in Z. f. Mf. 1847, p. 109, n. 9; 
Consp. n. 189; Pnewm. Mon. p. 129. 
Farcimen tortum var., Gray, Cat. Cycl. p. 30. 
Hab. Cuba. 
