COCHLOSTYLA-HELICOSTYLA. 185 



Whorls 4, scarcely convex, regularly increasing, the last scarcely 

 descending in front, distinctly carinated at the periphery, base 

 more convex. Aperture oblique, subrhombic-lunar, whitish inside, 

 with translucent bands. Columella oblique, compressed, subexca- 

 vated ; peristome blackish, margins subparallel, the upper expanded, 

 basal shortly reflexed. (Pfr.) Alt. 18, diam. '30 mill. 



Tukan Bessi Island. 



H. indusiata PFR., Mai. Bl. 1871, p. 121 ; Novit. Conch, iv, p. 

 71, t. 121, f. 3, 4; Monogr. vii. p. 355. 



Specimens of this species received through the kindness of MR. 

 J. H. THOMSON are before me. The surface where the cuticle is re- 

 moved, is opaque-white, faintly tinted with pink. The cuticle is 

 straw-yellow, with a narrow sutural brown line, extending both 

 above and below the actual suture, the portion above the suture be- 

 coming more prominent upward, and extending to the apex. At 

 the periphery there is a brown line, scarcely visible on one speci- 

 men before me, the same specimen lacking the columellar dark 

 tract, which is quite large on the other shell, of a purple-brown 

 color, and staining the greater part of the columella. There is a 

 very thin coat of hydrophanous cuticle above, with some slightly 

 more distinct creamy spiral lines. Below the periphery there is a 

 wide cream-white zone, and the base shows a number of narrow 

 bands of the same tint. 



C. THOMSONI Pfeiffer. PI. 29, figs. 1, 2, 3, 4. 



Imperforate, solid, depressed turbinate semiglobose; shining, 

 lightly striatulate ; bright straw-yellow, the earlier whorls pale pink- 

 ish ; suture bordered below by a brown line. Lip expanded, its 

 face and reverse blackish-brown. Whorl not deflexed at aperture. 



The form is more depressed than any specimens of C. collodes I 

 have seen, but, as in that species, the base is rather flattened. 

 Whorls 5, convex, the last very obsoletely angulated in front of the 

 aperture. Mouth white inside, quite oblique ; lip expanded, deep 

 brown. Columella arcuate, deeply entering. 



Alt. 22^, diam. 30 mill. 



" Tukan Bessi Island " (J. H. Thomson.) 



H. thomsoni PFR., Mai. Bl. 1871, p. 120 ; Novit. Conch, iv, p. 70, 

 t. 121, f. 1,2. 



