1 68 BRITISH FRESHWATER FISHES 



the Carp, are almost exclusively vegetarian, whilst 

 others, such as the Chub, are more predaceous. All 

 spawn in the spring or early summer, and apparently 

 but once a year, although the spawning season may 

 in some species be prolonged, or may be retarded 

 from various causes. At this season even the most 

 sluggish species become lively and sport at the sur- 

 face of the water; the fish usually crowd together 

 on quiet shallows, and seem to forget everything 

 except the occupation of the time, so that they may 

 readily be captured, and fall victims to the car- 

 nivorous fish and birds, which find them an easy 

 prey. The breeding males are sometimes remark- 

 able for their brilliant coloration ; usually they 

 acquire little tubercles on the head, which in some 

 species extend on to the back and sides of the body ; 

 another characteristic male feature is a thickening 

 of the first ray of the pectoral fin. 



After spawning, many of our Cyprinoids repair 

 to rapid shallows to recuperate, the more sluggish 

 species forming an exception to this rule; thence 

 they make their way to the feeding-grounds adapted 

 to the peculiarities of the species ; in the winter 

 all retire into deep water ; some fall into a 

 sort of torpor and lie huddled together in 

 shoals, or may even, like the Tench, burrow into 

 the mud ; others, like the Roach and Chub, 

 continue feeding whenever anything eatable is to 

 be found. 



The following synopsis, based on external char- 

 acters only, indicates the arrangement of the British 

 species adopted in this work, and may be used as a 

 key for their identification : — 



