SISTRUM. 180 



R. DTGITATA, Lam. PL 56, fig. 191 ; pi. 57, fig. 203. 



Shell whitish externally, columella, lip and interior of aper- 

 ture orange-color. Length, 1-1/5 inches. 



Central Pacific Ides. 



Var. LOBATA, Blainv. PI. 57, fig. 205. 

 Columella and lip dark chocolate-color. 



R. BICONTCA, Blainv. PI. 57. figs. 208-211. 



A revolving row of tubercles forms a shoulder on the bod}'- 

 whorl, and there is another median (and sometimes an inferior) 

 row of less developed tubercles ; these are usually white, but 

 sometimes dark brown; interspaces covered by brown revolving 

 ribs; more or less longitudinally plicate; aperture light violet 

 within ; two upper teeth of lip grouped together. 



Length, '75 inch. 



Philippines. 



PURPURA RTJFOSTOMA, LesSOll. 



This is evidently a Ricinulo, but the description does not 

 suffice for the recognition of the species. It is from the Gam- 

 bier Isles, and has never been figured. 



Submenus Sistrum, Montf. 



R. MOK.IJS. LMUI. PI. 57, figs. 213, 214. 



Usually white (sometimes orange-colored), the nodules black 

 (sometimes unoolored) : interior light violet. Length, '6-1 inch. 



Polynesia. 

 Var. ASPERUS. Lain. PL 57. figs. -215, 21(>. 



The longitudinal ribs which, in the type are scarcely apparent, 

 here become more pronounced, causing the tubercles to be nar- 

 rower and sharper. 



Philippines. 



Var. STRIATUS. Pease. PL 57, fig. 217. 



A depauperate form, with the longitudinal ribs almost con- 

 tinuous and developed at the expense of the tubercles. 



Length, '7 inch. 



Paumotu*. 



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