134 A HANDBOOK FOR SOUTHPORT. 



handsome shell, transparent horn colour, with three dark 

 brown spiral bands. Fine specimens are an inch and a 

 half high, and an inch and a quarter wide at the base, 

 with five or six very convex volutions. When the animal 

 is retracted it is closed by an operculum, a sort of trap 

 door, which should always be fitted in the shell when the 

 animal is taken out. It is both useful and ornamental in 

 an aquarium, the animal being beautifully sprinkled with 

 golden spots, and feeding mostly on the confervse growing 

 upon the sides of the glass. 



Bithinia tentaculata (Tentacled Bithinia). Common in most 

 of the ditches upon the Moss ; about a quarter of an 

 inch wide at the base and half an inch high, with five 

 rather flat volutions of dark brown or yellowish horn 

 colour, the aperture closed by an operculum. 



Valvata piscinalis (Stream Valve-shell). Shell globular, with 

 an elevated obtuse spire, the volutions well rounded and 

 distinct; the aperture closed by a valve or lid. Common 

 in the large drains upon the Moss. 



Valvata cristata (Crested Valve-shell). Not uncommon in the 

 same situations as the preceding, but very different 

 in appearance, being not more than an eighth of an 

 inch in diameter ; discoid, flat above, and concave or 

 umbilicate beneath. 



GASTEROPODA PULMONIFERA. 



Arion empiricorum (Black Arion). Common in the fields after 

 rain and in damp weather ; as moisture is an absolute 

 necessary of the creature's existence, it is rarely seen in 

 very dry weather. This is the common jet black snail ; 



