OE, GLIMPSES BENEATH THE WATERS. 



each imparting a diflferent flavonr. Tlie land 

 Molluscs were also much sought as a table delicacy, 

 a species of the large Garden-Snail being bred for 

 that purpose, and fed upon a prepared paste, which 

 so accelerated their growth that we learn, from the 

 industrious Pliny, of their attaining to enormous 

 dimensions ; the shells of some of the finest being 

 capable of holding eighty measures of water, called 

 quadrants. But in speaking of Molluscs, I must 

 principally confine myself to such as are suitable 

 for an Aquarium. 



Among the Sea-Snails of our own coast, which 

 are still eaten by the lower orders, is the Periwinkle, 

 considered by some superior in flavour to the 

 Oyster or Shrimp. This creature, the Littorina 

 Uttorea^ is one of the most useful creatures in an 

 Aquarium, cleansing it from all decaying vegeta- 

 tion, which is its natural food. The Periwinkle varies 

 much both in size and colour, the ground tone of 

 the shell being sometimes red, orange, or even scarlet, 

 sometimes with and sometimes without handsome 

 black bands. Such as are coloured in this attrac- 

 tive manner should obviously be selected as inmates 

 of the Aquarium, in preference to the dull-coloured 

 varieties ; and a few of the small yellow kind, 

 Littorina Uttoralis^ may be added by way of 



73 



