CYCLOPHORID”. 181 
Cyclostoma avena, Adams, Contr. to Conch. n. 1, p. 6; Pfr. Ie. 
n. 380, t. 46, f. 33-35. 
Tudora avena, Pfr. Consp. n. 378; Pneum. Mon. p. 258. 
Hab. Jamaica. 
XXIII. LEONIA. 
Operculum ovate, shelly, very convex externally, with a single 
whorl and the nucleus situated near the columellar margin. 
Shell ovate-conical; aperture ovate; peristome simple, slightly 
reflexed. 
Leonia, Gray, Syn. Brit. Mus. 1840, ed. 1842, p.91; Proc. Zool. Soc. 
1847, p. 181, n. 517; Cat. Cycloph. p. 34; Pfr. im Z. f. Mf. 1851, 
p. 168; Consp. p. 40; Pneum. Mon. p. 259. 
Cyclostoma (sp.), Auct. 
1. LEONIA MAMMILLARIS. B. M. 
Shell subperforate, ovate-elongated, rather thick, whitish or fulvous- 
flesh-coloured, marked often with an interrupted fuscous band 
along the suture; spire conic, with the apex nipple-shaped, . 
smooth; whorls 53, convex, the upper ones reticulated, the last 
one surrounded with impressed points and short lines, which 
are arranged into spiral series; aperture nearly perpendicular, 
obliquely ovate, angulated above, white within ; peristome rather 
thickened, white, scarcely expanded, with the margins joined 
by a continuous callus. Operculum typical. Length 18-22, 
breadth 9-10 mill. 
Cyclostoma mammillare, Zam. [ist. vi. p. 147, n. 20, Hd. Désh. viii. 
p- 359, n. 19; Delessert, Recueil, t. 29, f.10; Chenu, Lll. Conch. 
Livr. 73, t. 1, f. 10. 
Cyclostoma Voltzianum, Michaud, Cat. Test. Alg. p. 10, f. 21, 22; 
Pot. & Mich. Gal. Douai, i. p. 243, t. 24, f. 24, 25; Rossmiissl. in 
Wagn. Alg. iii. p. 260, t. 12, f. 14; Grells, Cat. Moll. terr. Esp. 
pod; T9510: 
Cyclostoma Volziana, Désh. in Lam. Hist. viii. p. 371, n. 39. 
Cyclostoma Woltzianum, Zerv. Catal. Alg. p. 63. 
Cyclostoma mamillare, Sow. Thes. n. 35, p. 102, t. 24, f. 45. 
Cyclostoma mammillare, Pfr. Jc. n. 126, p. 122, t. 14, f. 28, 29. 
Cyclostoma levigatum, Sow. ILSS. olim. . 
Cyclostoma Velascoi, G'rells, MLSS. olim. 
Leonia mammillaris, Gray, Cat. Cycl. p.34,n.1; Pfr. Consp. n. 379 ; 
-Pneum. Mon. p. 259. 
Hab. Spain and Algiers. 
