166 CHLOROSTOMA. 



Trochus nigerrimvs Gmel., Syst. Nat., xiii, p. 8572. — Philippi, 

 Conchyl. Cab., t. 10, f. 13. — Lischke, Jap. Meeres- Conchy I., p. 97, t. 

 7,f. 6, 7 (not Turbo mgerrimus GMEL.,=^3Io)wdonta nigerrima (Gm.) 

 (P*hil.) — Trochus niger, umbilicatus, etc., Chemnitz, Conchyl. Cab.,v, 

 p. 98, f. 1647. — T. niger Philippi, Conchyl. Cab., p. 369. — Fischer, 

 Coq. Viv., p. 372, t. 113, f. 4. — Chlorostoma corrugatum A. Adams, 

 P. Z. S., 1851, p. 182. — Chlorostoma undatella Gould, Proc. Bost. 

 Soc. N. H., 1861, p. 20. 



This species is most nearly allied to C. argyrostoma, and in the 

 sculpture differs from that form only in the rather smaller folds 

 above, and the lack of distinct spiral strise or lirse. It is smaller than 

 argyrostoma, more depressed, and always umbilicated. 



C. RusTicA Gmelin. PI. 25, figs. 1, 2, 3, 4. 



Shell umbilicate, conic, heavy, solid, chocolate-colored or brownish- 

 olivaceous; spire conical, more or less elevated; suture distinctly 

 impressed; whorls 6-7, moderately convex or nearly flat, sometimes 

 tumid just below the sutures, and either smooth or longitudinally 

 plicate, the folds usually obsolescent, and visible only for a short 

 distance beloAV the sutures ; spirally obsoletely striate ; body-whorl 

 obtusely angular at the periphery ; base nearly flat; aperture very 

 oblique ; columella with one or two teeth below, expanded above in 

 a white callus, which half surrounds the narrow, deep circular 

 umbilicus. Alt. 33, diam. 32 mill. 



Jaj)an. 



Trochus rusticus Gmel., Syst. Nat., xiii, p. 3572. — Philippi, 

 Co7ichyl. Cab., p. 48, t. 10, f. 11, 12.— Fischer, Coq. Viv., p. 163, t. 

 55, f. 1, t. 112, f. 2. — Llschke, Jap. Meeres- Conchyl., p. 97. 



Periphery less sharply carinate than in C. nordmanni and 0. 

 pfeifFeri ; less strongly sculptured than C. carpenter!, and not lirate 

 beneath ; more elevated than C. nigerrima and not nearly so finely 

 corrugated above. 



C. NiGRicoLOR Dunker. PL 26, figs. 21, 22. 



Shell conoid, imperforate, obsoletely striate, black ; whoi'ls plano- 

 convex, the last subangulate, ba.se convex, dull reddish or yellow- 

 ish ; umbilical callus green, pitted ; columella very oblique, uniden- 

 tate ; fauces smooth, pearly. Alt. 17, diam. 28 mill. (Dunker.) 



Japan. 



Trofhus nigricolor Dkr., Malak. Blut., 1860, p. 237, and Moll. 

 Jap., p. 22, t. 3, f. 2. — Lischke, Jap. Meeres- Conchyl., p. 100, t. 7, f. 



