INTA. 17 



Date, "I" white :md brown; m:ir_rin of umbilicus cn-iiu- 



l:ited. umbilical wall with :i <'rennl:ite<l , medial ril. 



I>i:un. Id IT mill. 



/:;! >Vr7,; Indian 0. : I 



T. <////v/, Mensch.; T. areolt, (Jmel.; T. /,rr^i>rr/,rn> / icula 1 

 Hillwyn, MIK!' T. Irwlatn, I>esh., are synonyms. 



V:ir. D1PBM8A, Phil. I'l. f>, figs. 78, 79. 



Shell very depressed ; color white with radiating brown 

 streaks, interrupted white l):inds on the strong ribs about the 

 periphery, umbilical crenulations and surrounding portion of 

 the base white. 



Var. PI-ANULATA, Hanley. PI. 5, fig. 77. 



Shell very depressed ; color brownish, with interrupted white 

 bands above the suture and on the two strong ribs about the 

 periphery. 



In the American Journal of Conchology (vol. v, p. 81, 1869), 

 AV. PL Pease states that the operculum of T. variegata from the 

 AVest (V-Kt of America, differs widely from that of the same 

 -s from Hawaii and the East Indies. He thus describes it : 

 " It is composed of plates disposed in the shape of a screw, of 

 three whorls. The plates are wide apart, and furnished on their 

 edges with short, stout bristles and the sides reticulated with 

 raised stri:i- "' (PI. 1, fig. 14-16). 1 have examined specimens of 

 the West Coast species, kindly loaned by Dr. Robert E. C. 

 Stearns, of the United States National Museum, and am. unable 

 to verily Mr. Pease's statement, the opercula being normal. 



T. DORSUOSA, Hinds. PI. 5, figs. 80, 81. 



ShelJ depressed ; whorls longitudinally striated, spirally sili- 

 cate and ten-ribbed, the rib on the periphery and that below it 

 being strongest; color reddish brown, confusedly blotched with 

 white, the two stout ribs about the periphery with interrupted 

 white bands; umbilicus moderate, crenulated, umbilical wall 

 with a spiral medial rib. Diam. lo mill. 



Pacific Islands. 

 T. CYLINDRICA, (Jm, 'I'm. PL 5, fig. 82. 



Shell conic, elevated ; whorls longitudinally striated, spirally 

 sulcate and ten-ribbed, the three ribs about the periphery being 

 strongest; color chestnut-brown, sparingly mottled with white 



