68 VANIKORO. 



V. Quoyi, Recluz, is a synonym. Many of the following 

 " species " are probably only slight and unstable modifications 

 of this form. 



Y. GrUERiNiANA, Recluz. PI. 29, fig. 62. 



Ribs stronger than in the preceding species, the spiral ridges 

 seen in their interstices ; umbilicus much wider. Diam. 15 mill. 



Philippines. 

 Y. RUGATA, A. Ad. PI. 29, fig. 63. 



Spire elevated, whorls rather strongly plaited, the deep inter- 

 stices spirally ridged, umbilicus moderate. Diam. 10 mill. 



Hob. unknown. 

 Y. CIDARIS, Recluz. PI. 29, fig. 64. 



Rather thin, clathrate with nearly equal longitudinal and spiral 

 sculpture, umbilicus narrow, almost closed. Diam. 22 mill. 



Philippines. 



Ribs not so strong as in V. cancellata, spire somewhat more 

 elevated. 



Y. LTGATA, Recluz. PI. 29, figs. 65-72. 



Rather thin, longitudinal sculpture low oblique folds, becom- 

 ing obsolete, spiral sculpture thread-like ; umbilicus moderate. 



Diam. 1 inch. 



Philippines, Paumotus. 



A little more elevated than F. cidaris, with larger umbilicus. 

 F. Petitiana (fig. 66), F. helicoides (fig. 68), and F. plicata, Recluz 

 (fig. 67), appear to me to be very slight modifications of the 

 type form, principally in the oblique ribtets being somewhat 

 more or less prominent; whilst in F. Deshayesiana (fig. 69), 

 F. Blainmlliana (fig. 71), and F. Spuleyetiana (fig. 70), of Re- 

 cluz the growth sculpture is obsolete or faint. Of this form 

 F. delicata, Pease (fig. 72), appears to me to be the young; it 

 comes from the Paumotus. 



Y. CLATHRATA, Recluz. PI. 29, figs. 73-77, 83. 



Rather thick, cancellating sculpture subequal, umbilicus mod- 

 erate. Diam. 10 mill. 



Hob. Polynesia, Australia, I. Bourbon. 



Nothing but the smaller size appears to distinguish this from 

 forms of the last species. N. granulosa, Recluz (fig. 74); F. 

 semiplicata, Pease (fig. 75); F. Gumingiana, Reel. (fig. 76), and 



