BRITISH MUSSELS. 



239 



placed in tanks where their reproductive powers can 

 be turned to account in feeding the other objects. 

 We have several British species of mussel, the prettiest 



Fig. 170. 



Common Mussel (Mytihts edulis). 



Fig. 171. 



Common Mussel, laid open to show the plated gills. 



of which is that called the 4< tulip mussel," a variety 

 of the common mussel, on account of the petal-like 

 stripes of colour which streak the shells. The com- 



