364 CYFRINID^E. 



difficult to name correctly ; the fins more or less bright 

 cinnabar red, particularly in those specimens which I have 

 seen from the Thames, Cambridgeshire, and Lough Neagh ; 

 dorsal and caudal fins not so bright in colour as the 

 fins of the under surface, but more inclining to reddish 

 brown. 



Walton says, " There is a kind of bastard small Roach, 

 that breeds in ponds, with a very forked tail, and of a very 

 small size ; which some say is bred by the Bream and right 

 Roach ; and some ponds are stored with these beyond be- 

 lief; and knowing men that know their difference call them 

 Ruds : they differ from the true Roach as much as a Her- 

 ring from a Pilchard. And these bastard breed of Roach 

 are now scattered in many rivers ; but I think not in the 

 Thames." Under the account of the Bream, he adds 

 " Some say that Bream and Roaches will mix their eggs and 

 melt together ; and so there is in many places a bastard 

 breed of Breams, that never come to be either large or 

 good, but very numerous." 



It is probable that the fishes here alluded to were the true 

 Rudd, and the second species of Bream, which have been 

 already described; and an opinion apparently prevailed, not- 

 withstanding the numbers in which they existed, that they 

 were hybrids. The instances in which animals in a truly 

 unlimited natural state make selections beyond their own 

 species are probably very rare. Hybrids and permanent 

 varieties are the consequence of restriction and domestication, 

 and I confess my doubts of the existence of hybrid fishes. 



