76 TROCHUS. 



lightly concentrically marked around the center; aperture rounded, 

 outer and basal margins crenulated within ; columella bearing a 

 small tooth above and below, concave between them, deeply entering 

 the umbilicus, but inserted on its edge ; umbilicus rather deep, 

 smooth within, bordered by an irregularly crenulated rib. 



Alt. 11, diam. 14 mill; alt. 8^ diam. 9 mill. 



Mediterranean and Adriatic Seas. 



Monodonta jussicei Payr. Cat. Annelides et Moll. Corse, p. 136, t. 

 6, f. 24, 25 (1826). — M.jussieui Philippi, Enum. Moll. Sicil. ii, p. 

 157 (1844).— Troc/ms jussievi Phil., Conchyl. Cab., p. 81, t. 14, f. 

 11. — Fischer, Coq. viv., p. 238, t. 82, f. 1. — Clanculus jussieui Bucq., 

 Dautz. et Dollf., 3Ioll. Mar. du Rouss., t. 50, f. 13-20, p. 413.— 

 Clanculus hlainvillei Cantraine, Malac. Medit. et litt. t. 6, f. 14, 14a ; 

 Bull. Acad. Brux., ix, p. 344. — Trochus glomus Philippi, Enum. 

 Moll. Sicil., ii, p. 157, t. 25, f. 16 ; Conchyl. Cab. p. 82, t. 14, f. 15. 



To be consistent, Payrandeau's original spelling of this name ought 

 to be revived ; but since the emended form used by Philippi has 

 been adopted by all modern authors we would perhaps in this case 

 lose rather than gain by a rigid adherence to principle. The species 

 was named in honor of M. Adrien de Jussieu, " professeur au 

 Jardin du Roi." 



It is a variable form in size, coloration and sculpture ; the surface 

 is remarkably smooth and shining for a Clanculus. The following 

 color varieties are described by Messrs Bucquoy, Dautzenberg and 

 Dollfus. (Moll, du Roussillon, p. 415.) 



Var. GLOMUS Phil. (pi. 19, figs. 9, 10). More decidedly lirate 

 iibove than the type. This is a transition form to T. cruciatus. 



Var, striata Monts. Small, polished, under a lens showing fine 

 spiral lines. (Gulf of Gabes, Tunis.) Var. blainvillei (pi. 11, 

 fig. 36). Conspicuously tessellated. Var. roseo-carnea Monts. 

 Roseate or violaceus in color. 



T. spadiceus Philippi. PI. 9, figs. 97, 98 ; pi. 11, figs. 52, 53. 



Shell umbilicate, conoid, thick, shining; whorls 5i, convex, the 

 first vivid rose-color, following chestnut-brown, subcanaliculate at 

 the suture, in the middle subangulate, minutely spirally cingulate, 

 the ridges about 9 on the penultimate whorl ; last whorl carinated, 

 slightly convex beneath and paler, white and brown maculate, con- 

 centrically marked with about 9 delicate lira?, the interstices radi- 

 ately striate ; aperture subtrapezoidal, plicate within ; lip double, 



