NERITELLA. 381 



Syn. Neritina, Lam. Clypeolum, Recliiz. Nereina, 

 Crist, and Jan. Lainprostoma, Rqfi^i., not Swains. 

 Chernites, Gistel. 



Ex. N. pulligera, Linnceus, pi. 42, fig. 2. Operculum, 

 N. pulligera, fig. 2, a, 2, h. Shell, N. pulligera, fig. 

 2, c. 



The Neritell(B are tolerably numerous in species ; 

 they are inhabitants of fresh water, and are usually 

 covered with an epidermis ; some among them are 

 found crawling on the stones in shallow water, others 

 live in deeper water, half buried in the mud, some in 

 brackish, and others even in salt water; some are 

 amphibious, clinging to the roots of Nipah palms and 

 other trees on the margins of rivers, while a few in- 

 habit the foliage of tall trees that overhang ponds 

 and rivulets. The genus Neritella, as restricted, is 

 characterised by the shell being transverse, elliptical, 

 or hemispherical ; the spire lateral or none ; the inner 

 lip septiform, flattened, and striolate, with the margin 

 finely denticulate : with one or two exceptions, they 

 are not found in the frigid or temperate zones, but are 

 extensively distributed in every other part of the world. 



Species of NeriteUa. . 



asperulata, Recluz. porcata, Gould. 



Beckii, Becluz. Powisiana, Recluz. 



bicanalis, Phil. pulligera, Lirm. 



canalis, Soiv. punctulata, Lam. 



cliolerica, Gould. Rossmassleriana, Recluz. 



Knorri, Recluz. rubella, Milll. 



labiosa, Sow. sanguinea, Soiv. 



pennata. Born. squamsepicta, Recluz. 

 Petitii, Recluz. 



