CHAPTER XXXVIII: THE BLACK SNAILS. 

 MARSH SNAILS 



Family MELANiiOi^ 



Shell spiral, turreted; spire often worn; epidermis dark, 

 thick; aperture notched or chambered in front; outer lip sharp; 

 operculum horny, spiral. 



Animal with broad, short, foot; broad, non-retractile snout; 

 tentacles far apart, bearing short eyestalks; tongue long, slim, 

 with seven series of many-cusped teeth; mantle margin fringed; 

 gill of stiflF, cylindrical plates. Reproduction often viviparous. 



A large family inhabiting fresh water lakes and rivers, in 

 warm regions, chiefly of the Old World. 



Genus MELANIA, Lam. 



Shell with acute apex, its whorls ornamented with spines or 

 striations; aperture oval, pointed above. Four hundred species, 

 distributed over Southern Europe, India, Philippines, Pacific 

 Islands, in swift tidal rivers, especially in rapids. 



The Melanias include forms with cancellated, tubercled and 

 smooth shells. They range from globose to needle-like forms. 

 The largest is under three inches long. Many species have their 

 shells decollated — broken off at the apex. The finest species 

 are Philippine. 



The Acorn Black Snail (M. glans, Busch) is smooth, oval, 

 olive-hued, with a depressed spire; the body whorl and the 

 aperture are both very large. Length, i inch. 



Habitat. — Java, Philippines. 



The Bristly Black Snail (M. setosa. Swains.) is globose and 

 has its spire set with a spiral row of erect sharp spines. The black 

 or green exterior contrasts with the pale lip and throat. Length, 

 i^ inches. 



Habitat. — Philippines, Fiji Islands. 



M. hastula, Lea, is fawn-coloured and long and tapering 



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