NERITA. 19 



Section Nerita, Lain. 1799 (sensu stricto). 



N. ALBiciLLA, Linn. PI. 2, figs. 21-26. 



With wide, fiatly convex ribs, separated by narrow sulci, whitish, 

 yellowish or orange color, densely or sparsely clouded, maculated 

 or interruptedly or irregularly banded with black ; aperture white, 

 the columellar area tuberculated, with small teeth on the middle of 

 the margin, outer lip with numerous small teeth. 



Red Sea, Indian Ocean, Natal, Singapore, China, Philippines, 

 Viti Is., etc. 



It is N. sanguinnlenta, Menke, N. venusta, Phil. (fig. 24), JSf. 

 marmorata. Reeve (not Hombr. and Jacq.), =^ N. crassilahrum, 

 Smith, 'IN. marginata, Gmel., N. cornea, Forsk., N. Erythrcea, 

 Desh., and j\^. Forskalii, Eecluz (figs. 25, 26). 



N. PLEXA, Chemn. PI. 2, figs. 27, 28. 



With rugose or somewhat nodose spiral ribs, alternately smaller, 

 whitish, maculated with black ; aperture whitish, black spotted on 

 the fimbriated outer margin, lij^ numerously jilicate-dentate within, 

 columellar area with a raised plicate outer border, the face numer- 

 ously granulate, the centre of the margin two-toothed. 



Diam. 30-45 mill. 



East Africa, Cape, Madagascar, India, etc. 



The synonyms are N. costata, Schum., N. te.vtiUs, Gmel., N. chlo- 

 rostoma, Lam. (fig. 28). 



N. ExuviA, Linn. PL 2, fig. 29. 



With strong, rugose, high ribs, broadest at the top, or somcAvhat 

 overhanging, the intermediate sulcatious deep, often in the larger 

 specimens with a median thread-like, rugose, but much smaller rib- 

 let in each, the ribs blackish or obscurely maculated, the sulci grey- 

 ish or yellowish grey, with zigzag black stripes ; aperture white, 

 the columellar area, including the raised border, covered by very 

 numerous small granulations. Diam. 30-35 mill. 



Indian Ocean, East Indies, Philipj^ines. 



It is N. Malaccensis, Lam. N. chlorostoma. Lam., which I have 

 referred to the preceding species. Dr. von Martens places here ; in 

 the outer border of the columellar area it combines the characters 

 of both, but its exterior ornamentation is, I think, decidedly that 

 of N. ple.ra. 



