GIBBULA. 207 



gradate; whorls subbicarinate, smooth above and flat; aperture 

 subquadrangular ; umbilicus open, smooth. 

 Alt. 12, diam. 15 mill. {Orh.') 



Canary Is. 



T. candei d'Orb., Hist. Nat. lies Canaries, Mollusques, p. 82, t. 6, 

 f. 21-23.— Philippi, Conchyl. Cab., t. 34, f. 15. 



Known to me only by the description and figures of Orbigny. 

 G. RiCHARDi Payraudeau. PL 32, figs. 54-56. 



Shell umbilicate, conoidal, olivaceous or yellowish, ornamented 

 with obliquely longitudinal tawny stripes; entire surface smooth; 

 spire short, conical; sutures deeply impressed; whorls 5, quite 

 convex, the last flattened and sloping around the upper part, 

 very obtusely subangular around the jDeriphery ; aperture large, 

 very oblique ; outer lip thin, acute, very narrowly margined 

 with yellow, succeeded by a line of black, within which lies a band 

 (about 2 mill, wide) of opaque white ; columella arcuate above, 

 partly surrc)unding the umbilicus with a white callus, straiglitened 

 in the middle ; umbilical tract large, white, funnel-shaped, bounded 

 by a carina. Alt. 15, diam. 17 mill. 



Mediterranean and Adriatic Seas. 



Monodoata richardi Payr., MoU. de Corse, p. 138, t. 7, f. 1, 2. — 

 Trochus Richardi Philippi, Conchyl. Cab., p. 189, t. 29, f. 4, 5, 7. 

 —Fischer, Coq. Viv., p. 142, t. 48, f. 1.— B., D. et D., MolL du 

 Eoass., p. 399, t. 47, f. 6-13. — Phorcus margaritacens Risso, Hist. 

 Nat. Ear. Merid. iv, p. 133, t. 4, f. 47. — T. radiatm Anton, Ver- 

 zeich., p. 57 (Teste Philippi). 



Type of Risso's genus Phorcus. A species peculiarly attractive 

 in appearance ; it is smoother than its allies, and striped upon an 

 olive-yellowish ground with a very pleasing and unusual tawny or 

 cadmium orange hue. Rarely unicolored olivaceous specimens occur, 

 or shells with a ground color of crimson. 



G. DiVARiCATA Limie. PL 33, figs. 74, 75, 76, 78, 79. 



Shell imperforate or narrowly perforate, conoidal, very thick 

 and solid, cinereous, yellowish or green, longitudinally marked with 

 rose-red lines, often oblique or broken into square dots ; spire more 

 or less elevated, its outlines rather convex ; whorls about 6, encircled 

 by numerous liruhe, the upper ones flattened, sutures slightly im- 

 pressed, but scalariform specimens with deep sutures are frequent ; 

 last whorl rounded at the periphery and on the base ; aperture 



