42 HELIX CORYDA. 



gradually widening, slightly convex, the last scarcely deflexed an- 

 teriorly, obtusely sub-angular at the periphery ; flattened beneath ; 

 aperture oblique, transverse ; peristome thin, margins scarcely con- 

 verging, outer and basal lips slightly expanded, columellar margin 

 white, very oblique, nearly straight, flat, thickened somewhat within, 

 inserted in the center of the axis. 



Alt, 10, diam. 16 ; Alt. 8*,diam. 17 mill. 



Jamaica. 



H. blandiana, Ad. Contr. to Condi, no. 7, p. 107. REEVE, Conch. 

 Icon. f. 303. PFR. Monogr. iii, p. 193. 



The gradual increase of the whorls is the most notable feature of 

 this shell. 



H. PHJEOGRAMMA, Pfeiffer. PI. 18, figs. 16-17. 



Covered perforate, orbicularly convex, shining, rather glabrous, 

 with radiating rich chestnut lines above and a castaneousfascia on 

 the base ; whorls 4, scarcely convex, the last obsoletely angulated, 

 base rather flattened ; aperture very oblique, rotund-lunar ; peris- 

 tome labiate with chestnut within, margins converging, upper mar- 

 gin a little expanded, basal dilated, reflexed, appressed. 



Alt. 82, diam. maj. 15. ruin. 12s mill. 



Habitat unknown. 



H. phceoyrammePFH. Symbolceui, p. 72, (1846); Monographia i, 

 p. 285. REEVE, Conch. Icon. f. 299. 



Known to me only by the above description and Reeve's fig- 

 ures. 



Section V. CORYDA Albers, 1850. 



Coryda ALB. DieHeliceen 1850, p. 100. H & A. Ad., Gen. Rec. 

 Moll, ii, p. 198. and of authors generally. Histrio PER. Mai. 

 Blat. 1855, p. 185 ; he. cit. 1877, p. 8. PEEIFFER-CLESSIN Nomen- 

 clator, p. 159, 1881. 



Coryda consists of snails essentially similar to Dialeuca , differing 

 in the heavier shell, abruptly deflexed whorl at the aperture, and 

 more varied coloration. The type is H. alanda Fer. Histrio of 

 Pfeiffer is completely synonymous ; for H. dennisoni, its type, is 

 barely specifically distinct from H. alauda. 



H. ALAUDA Ferussac. PI. 16. 



Imperforate, globose-depressed or conoidal, solid, heavy, strong, 

 opaque, somewhat shining, slightly irregularly marked by growth 

 lines ; color very mutable, (see below) ; spire depressed, dome-shaped 



