u CHARACTERISTICS OF VALUABLE MARINE FISHES 51 



in a large number of families. The well-known fresh-water 

 perch and a number of species resembling it form one family. 

 In the perch and others there are two fins on the back, the front 

 one being supported entirely by spines. In all fishes of this 

 division when there are separate fins on the back the first 

 always contains spiny rays only, while most of the rays in the 

 rest are jointed and soft. In the perch-like fishes there are no 

 scales over the longitudinal fins, no barbels, and the teeth arc 

 small and pointed. There are a great number of different kinds 

 of fishes in the family, some of which live in fresh water and 

 others in the sea. The latter are all coast fishes, and occur all 

 over the world in temperate regions and the tropics. The only 

 marine species of any great importance in Britain is the bass 

 (Fig. 3), sometimes called salmon-bass on account of its 

 elongated shape and bright silvery skin. It has no close re- 

 lationship with the salmon, as is at once evident from its spiny 

 first dorsal fin and the situation of its second pair of side fins 

 beneath the breast fins. 



The sea breams (Fig. 15) resemble many species of the perch 



FIG. 15. The Common Sea Bream. 



family in the character and arrangement of their fins, but are 

 distinguished by their peculiar teeth, of which those in front have 

 broad cutting edges and those behind round tops formed for 

 crushing. They are all coast fishes, and many different kinds 

 occur more or less commonly on the more southern shores of 



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