384 



NERITIDyE. 



Sub-gen. altma, Recluz. 



Shell depressed, sub-orbicular, with the upper extremity of 

 the outer margin prolonged into a lateral wing; spire sub- 

 posterior and lateral ; inner lip septiform, margin finely 

 denticulate. 



fequinoctialis, Morel. 

 Eahiensis, Phil. 

 globosa. Sow. 

 granosa, Soiv. 

 intermedia, Soiv. 



Jordani, Soic. 

 latissiraa, Brocl. 

 Nuttallii, Hecluz. 

 Oweniana, Gray. 



Sub-gen. neriptekon, Lesson. 



Shell catilliform, with the two extremities of the outer margin 

 prolonged into lateral auricles ; spire sub-posterior and lateral ; 

 inner lip septiform ; margin finely denticulate. 



auriculata, Lam. 

 biauriculata, Recluz. 

 dilatata, Brod. 

 florida, Recluz. 

 Lamarckii, Desh. 



Mauritise, Less. 

 navicularis, Morch. 

 subauriculata, Recluz. 

 Tahitensis, Less. 



Genus CLITHON, Montfort. 



Shell sub-globose or sub-orbicular, whorls usually 

 crowned with spines ; aperture semilunar ; inner lip 

 septiform and denticulate, one of the median teeth 

 always stronger and more prominent than the others, 

 obtuse, and forming a spiral internal ridge ; outer lip 

 more or less emarginate in the middle. 



Syn. Cliton, Less. Corona, Recluz, 



