The Black Snails. Marsh Snails 



like the auger shells. Its whorls are few, cross-ribbed and some- 

 what rounded. Length, 2 to 3 inches. 



Habitat. — Philippines. 



M. laevissima, Sby., is a solid, stout, smooth, conical shell, 

 thick-lipped, ashy blue streaked with purple. Length, i to 2 

 inches. 



Habitat. — Mexico. 



Genus PALUDOMUS, Swains. 



Shell conical or globose; aperture large, round; peristome 

 continuous; columella callous; operculum spiral; animal like 

 Melania. Twenty-five species, found in India and Ceylon. 



Gardner's Paludomus (P. Gardneri, Rve.) is the most 

 characteristic species. The orbicular-ovate shell is deeply sculp- 

 tured by blunt, spiral ridges, alternately large and small; the 

 mouth is large, the spire depressed; colours, black outside, white 

 inside, with purple-stained lips. Length, i^ inches. 



Habitat. — Ceylon. 



The Mail-Clad Paludomus (P. loricatus, Rve.) is a stony, 

 globose shell, wide mouthed like a Nerite, which it otherwise 

 closely resembles. The revolving ribs are set with triangular 

 points, like diminutive shark's teeth. The brown exterior con- 

 trasts sharply with the white interior. Length, i^ inches. 



Habitat, — Ceylon. 



185 



