GREY MULLET. 215 



period, and ascend a river, like a salmon. Possibly 

 this irregular act on the part of the grey mullet and 

 some other fish may be to get rid of superfluous 

 parasites, for the fish always return apparently better 

 for the change. This fish has been a deserved 

 favourite at the table since the time of the Romans. 

 Its food mainly consists of dead and decaying vege- 

 table matter, eked out occasionally by worms, small 

 crustaceans, mollusca, &c. It is very fond of browsing 

 on the green confervas in the tank, hence it is a valu- 

 able vegetable scavenger in aquaria. Not unfre- 



Fig. 144. 



Black Sea-bream (C<intharus griseus). 



quently it attains a weight of fifteen pounds, although 

 its average length is about eighteen inches. The black 

 sea-bream (Cantharus griseus) is another handsome 

 aquarium fish, possessing a bright silvery hue, and 

 remarkable for its delicate spreading pectoral fins. 



