TORINIA. 21 



radiateLy striated, spirally silicate; umbilicus wide, margin 

 numerously crenulated, umbilical wall with a spiral rib. 



Diam. 9 mill. 



Straits of Macassar. 



Easily known by the flatness of the shell and the two very 

 prominent ribs about the periplieiy. Hanley's figure of this 

 species in Thes. Conch, is a very poor representation. 



T. DISCOIDEA, Pease. PI. 6. fig. 6. 



Shell very depressed ; whorls finch' granulated, slightly chan- 

 neled at the suture, spirally sulcate and ribbed, the two ribs of 

 the periphery being very strong; color white, clouded with very 

 faint chocolate; base rounded, umbilicus lightly crenulated, 

 channeled, umbilical wall with two spiral ribs. Diam. 63 mill. 



Paumotus. 

 T. ASPERA, Hinds. PL 6, figs. 7, 8. 



Shell discoidal, slightly conical ; whorls rough, tubercular, 

 radiately striated, spirally sulcate, strongly ribbed on the per- 

 iphery ; base rounded, umbilicus very wide, its margin numer- 

 ously crenulated. Diam. 94 mill. 



Straits of Macassar. 



The t} r pe of this species was a dead shell and consequently 

 without color. 



T. ARCIIIT^:, Costa. PI. 6, figs. 9, 10, 11. 



Shell discoidal ; whorls flat above, rounded below, channeled 

 at the suture, longitudinally and spirally sulcate, crenulated ; 

 color yellowish white ; umbilicus very wide, margin finely crenu- 

 lated. Diam. 7 '5 mill., 



Mediterranean. 

 T. SOWERBYI, Hanley. PL 6, figs. 12, 13. 



Shell nearly discoidal ; whorls channeled at the suture, with 

 four granose cingulre, the upper three of which are equal and the 

 fourth greater, last whorl with 13-14 cingulse, periphery sloping 

 off, not biangulate ; color yellowish white, clouded or varic gated ; 

 umbilicus moderate, its margins crenulated. Diam. 6 mill. 



Mediterranean, Tunis. 



This species is distinguished from the preceding by the much, 

 more narrpw umbilicus. 



