90 HELICID^. 



FAMILY III.— HELICID-ffi. 



Body elongated, spirally coiled ; mantle covering the neck, 

 sometimes, though rarely, in the form of a demi-shield which is 

 provided with a lobe ; tentacles usually 4, rarely 2, retractile ; 

 foot oblong, distinct from the body. 



Shell spiral, usually large enough to contain the whole body. 



The British members of this extensive family are 

 divided into eleven genera. 



GENUS I.—SUCCFNEA* DRAPARNAUD. 



Body glutinous, thickish, usually incapable of being entirely 

 covered by the shell ; mantle thin, entire ; tentacles 4, upper 

 pair conical, thickish at their base, lower pair very slender and 

 short ; jaw smooth ; lateral teeth serrated ; respiratory orifice 

 placed on the right side ; foot oblong, large. 



Shell dextral, oblong-ovate, fragile, of an amber-colour ; spire 

 short ; 7nonth large. 



It has already been stated that the LimnceidcBy 

 though essentially aquatic animals, are capable of 

 living for a considerable period out of water, some 

 of them, indeed, at times voluntarily leaving it. With 

 respect to the molluscs now under consideration the 

 case is exactly reversed. The Succinece, though es- 

 sentially terrestrial, can, and do occasionally, remain 

 submerged ; and hence they form a connecting link 

 between the truly aquatic and the truly terrestrial 

 molluscs. 



The SitccinecB frequent marshy places, climbing up 

 and resting on the stalks of flags, rushes, and other 

 aquatic plants. During the time of drought they 



* Amber-coloured. 



