CHAPTER XLIV: THE APPLE SNAILS. FLASK 



SNAILS 



Family Ampullariid^ 



Shell globular, with large body whorl ; spire short, depressed, 

 sometimes making the coil flat; aperture somewhat expanded; 

 operculum concentric. Animal with long siphon, left gill much 

 smaller than right; muzzle ending in two long feelers; tentacles 

 very long. 



An amphibious family of tropical distribution in both hemi- 

 spheres, corresponding to the Paludinidae in ponds and streams 

 of temperate regions. The gills lie in a large, partially closed 

 breathing cavity, which adapts the mollusks to life out of water. 

 In dry seasons they bury themselves in mud; indeed, they survive 

 removal from water for months, breathing air, but probably 

 keeping the air chamber moist. The typical genus has a green, 

 shiny epidermis. 



The large eggs are laid in limy capsules, which adhere in 

 round masses to the stems of water plants. When fresh they 

 are beautifully coloured, crimson, pink or bluish green. 



Genus AMPULLARIA, Lam. 



Lip continuous, reflected, thickened inside, operculum horny, 

 with shelly coat outside. A large genus of striking coloration 

 and size. 



The Giant Flask Shell ( A. gigas, Spix), as large as a man's 

 clenched fist, is a formidable snail. The great aperture almost 

 conceals the rest of the shell with its continuous flaring rim, as 

 one looks down into its blue-banded depths. The spire is deeply 

 channeled and sunken well into the inflated body whorl. The 

 horny olive surface bears many narrow bands of green. The pit 

 is deep; the lip yellowish and spotted. Diameter, 4 to 6 inches. 



Habitat. — Brazil. 



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