230 BRITISH FRESHWATER FISHES 



The six species of the Bass genus inhabit the 

 North Atlantic and Mediterranean and the rivers 

 which flow into them, and it is interesting to note 

 that whilst the two European species are marine, 

 only ascending rivers occasionally, two of the North 

 American forms are anadromous, spawning in fresh 

 water, whilst the remaining two have become per- 

 manent freshwater residents. 



The Bass shows many structural resemblances to 

 the Perch, from which it is at once distinguished by 

 the coloration, which is nearer to that of the 



FIG. 21. Bass. 



Salmon, being silvery, with the back bluish grey 

 or olive ; a dark spot is present on the opercle, and 

 small scattered blackish spots may be present in 

 the young. The Bass also differs notably from the 

 Perch in the stronger and fewer spines, eight to ten 

 in number, of the spinous dorsal fin, and in having 

 three anal spines instead of two. 



This species grows to a much larger size than 

 the Perch, attaining a length of more than 3 feet 

 and a weight of nearly 30 Ibs., although fish of half 

 that size are considered large. It is found in the 

 Mediterranean and on the Atlantic coasts of Europe, 



