MARINE MOLLUSCS 



216 



sible that but few of our readers have ever taken the trouble to place 

 the animal in a vessel of sea water, either obtained direct from the sea 

 or artificially prepared, for the purpose of studying its movements 

 or other habits ; and it will be well to remember that this and several 

 other species of edible molluscs which reach our towns alive may be 

 very conveniently studied 

 at home, and often at 

 times and seasons when 

 work at the sea-side is 

 undesirable or impos- 

 sible. 



The edible species re- 

 ferred to lives in banks 

 of sand or mud, buried 

 just below the surface, 

 and frequently in spots 

 that are exposed for seve- FlQ- ug.i. Cardium pygmasum. 2. Car- 

 ral hours between the dium fasciatum. 3. Cardium rusticum 

 tides. They are usually 

 obtained by means of a rake similar to that used in our gardens. 



On the coasts of Devon and Cornwall we find a much larger 



FIG. 147. Cardium aculeatum 



species, also valued as an article of diet, and known locally as the 

 Prickly Cockle (C. aculeatum). Its shell is beautifully formed, the 



