NERITINA. 63 



N. GRANOSA, Sowb. PI. 21, figs. 51, 52. 



Much depressed, covered with warts throughout, arranged some- 

 what in quincunx order, rayed on the sides ; aperture bluish white, 

 radiated and speckled with darker short lines and spots, columellar 

 area whitish or more or less tinged and colored with yellow, varying 

 to reddish orange. Diam. 30-45 mil]. 



Sandwich Is. 



N. papillosa, Jay and N. gigas, Lesson are synonyms. 



Subgenus CLITHON, Montfort. 1810. 



When the spines are developed, as they usually are, there is no 

 difficulty in determining these shells; but occasionally the same 

 species is spineless, and even some of the species referred here 

 appear to never develope spines, in which cases they are only 

 separable from Clypeolum by the characters of the operculum. 



N. LONGISPINA, Reel. PL 23, figs. 3-5. 



Epidermis varying from rather dark brown to nearly black, the 

 lighter colored specimens often with black lines and bands, surface 

 plicately rugose, with a series of long, cylindrical spines on the 

 shoulder; aperture bluish white, showing the exterior bands, colu- 

 mellar area flattened, smooth, usually whitish or posteriorly tinged 

 with yellow, terminated by a distinct rounded line, margin incurved 

 in the middle and edentulous or minutely dentate. 



Diam. 15-30 mill. 



Mauritius, Isle of Bourbon, Rodriguez, Madagascar. 

 It is N. corona, Linn, in part, N. coronata, Leach. 



Var. MAUEITIANA, Morelet. Fig. 5. 



Spines not developed. N. despiuosa, Mouss. is a synonym. 



N. SPIBOSA, Budgin. PI. 23, figs. 6, 7. 



Rather smooth, with a few wrinkles, shining, light yellowish 

 brown with irregular black spiral bands, and a corona of moderately 

 long, subcylindrical black spines; aperture bluish white, showing 

 the bands, columellar area flattened, distinctly circumscribed pos- 

 teriorly, often tinged with yellowish, deepening into reddish-orange 

 behind, margin a little incurved but scarcely dentate in the middle. 



Diam. 15-20 mill. 



Taheiti. 



