82 NAVICELLA. 



synonyms N. jyulehella (fig. 56) and N. insignis, Reeve (fig. 55), var. 

 oblonga. Martens, and its synonym N. maculifera, Mousson, var. 

 compressa, Mart., and its synonym N. Eiitrecasteauxi, Reel., (fig. 59) 

 N. reticulata, Reeve (fig. 62), inclnding, N. eximia, Reeve (fig. 61) 

 and its var. compressa, Martens (fig. 67), of which N. Livesayi, Dohrn 

 is a synonym, and N. ccerulescens, Reel. (figs. 63, 65), with its syn- 

 onyms N. plumhea, Sowb., N. comjoressa, Benson, and N. orientalis, 

 Reeve (fig. QQ). 



Section Stenopoma, Gray, 1<S67. 



N. LiNEATA, Lam. PI. 29, fig. 58. 



Shell compressed elliptical, light yellowish, with a radiating pat- 

 tern of chestnut or purplish longitudinal reticulations, forming tes- 

 sellations and triangular markings of the lighter color, very thin, 

 translucent, interior showing all tlie exterior markings, light bluish 

 or yellowish. L. 25 mill. 



Philippines, Viti Is. 



Von Martens unites this species with N. tessellata, Lam., and I 

 have no doubt that he is correct, but the latter might with equal 

 propriety be united with N. sub orbicular is, etc. : in fact, the charac- 

 ters in this group anastomose in every direction. 



N. navicula, Fer., and N. pictinxUa, Garrett (fig. 60) are syn- 

 onyms : in the latter the ground color varies from yellow to pale 

 purple, and the tessellations are often replaced by distinct radiating 

 bands. 



Unfigured species of Navicella. 



N. APONOGETONis, Valil. East Indies. 



N. EXCELSA and IST. Moreletiana, Gassies. JSfew Caledonia. 



These two have the interiors only, figured, and those have no 

 characters. 



Family NERITOPSIDM 

 Genus NERITOPSIS, Grat, 1832. 



N. RADULA, Linn. PI. 29, fig. 68. 



Shell opaque, thick, white, with thick, close, beaded, spiral ribs, 

 the narrow interstices pitted ; outer lip fluted by the ribs. 



Alt. •75-l"5 inch. 



Singapore, Java, Mauritius. 



