CHLOROSTOMA. 183 



lip is thickened within, and this thickening where it unites with the 

 cohnnella, leaves a deep furrow resulting from the continuity of the 

 margin of the outer lip with the border of the umbilicus. Above 

 the columella is continued in a lobe partly surrounding the umbili- 

 cus. The color is brownish-red, almost wine-colored, with white 

 flecks. Alt. 15, diam. 19 mill. (Philippi.) 



Panama. 



T. panamensis Phil. Zeitschr. f Mai. 1848, p. 127 ; Conchyl. 

 Cab., p. 311, t. 44, f 15. 



C. cooKSONi Smith. PL 60, figs. 12, 13. 



Shell deeply umbilicated. suborbicular, slightly conoidal, brown, 

 variegated with rosy, painted with white lines articulated with 

 black ; whorls 4j, nearly smooth, slightly convex, sculptured with 

 few delicate spiral strife ; last whorl convex above, slightly depressed 

 beneath the suture, at the periphery flattened and biangulate : base 

 nearly flat, delicately spirally striate, around the umbilicus encircled 

 with a shallow groove ; umbilicus white, deep, surrounded by white 

 callus forming a tooth at the base of the columella ; aperture sub- 

 orbicular ; columella arcuate, joined to the whorl by a callus. 



Alt. 4, diam. 8 mill. (Smith.) 



Charles Id. ; Galapaffos. 



This shell is deeply umbilicated, elevately orbicular, convex 

 above, only slightly conical, and flat beneath ; the last whorl is 

 flattened at its middle, and this produces a double angulation, 

 which, however, is not very cons])icuous. Thei'e is also a faint de- 

 pression a little below the suture. The coloration of this species is 

 not very definite ; the upper surface is blotched irregularly with 

 pink and brown, and some spiral articulated lines; the base is a 

 trifle paler ; the only sculpture consists of fine spiral striations, 

 which are most conspicuous on the base ; the callus which surrounds 

 the umbilicus is whitish, and terminates in a faint tooth on the 

 columella, and is bordered by a shallow sulcus on the whorl. The 

 columella terminates above in a callosity which extends upward 

 some distance on the whorl, and also spreads out within the aperture. 

 T. occidtus of Philippi bears a faint resemblance to this form, but is 

 more conoid, and more strongly sculptured. (Smith.) 



Charles Id., Galapagos. 



Tr. (Omphalitis) cooksoni Smith (in Giinther, Zool. coll. H. M. S.. 

 'Peterel'), P. Z. S. 1877, p. 71, t. 11, f. 7. 



