400 CYPKINIDK. 



of the British Fishes, says, " In the river Thames the finest 

 Roach are caught about the middle of May or early in June, 

 when those fish come up in shoals from the sea to deposit 

 their spawn in the higher parts of the river ;" but the Roach 

 in this instance come from the direction only in which the 

 sea lies, not, I apprehend, from the sea itself: the attempt 

 to gain a higher station in the river, where the oxygen is in 

 greater quantity, is analogous to the movement previously 

 noticed as occurring in Loch Lomond, and also in the allied 

 species, L. idus and dobula, previously described ; but I 

 have never known a Roach to be taken in the sea into which 

 the fish had entered voluntarily. Montagu, in his MS. re- 

 ferring to Mr. Donovan's statement of this migration from 

 the sea, states his belief that Mr. Donovan was mistaken, 

 and expresses also his belief that the Roach could not exist 

 in sea-water at all ; quoting the following fact which came 

 under his own observation : In a small river that runs into 

 a large piece of water of nearly two miles in extent, close to 

 the sea, on the south coast of Devon, there is no outlet but 

 by means of percolation through the shingle that forms the 

 barrier between it and the sea : in this situation Roach thrive 

 and multiply beyond all example. About eight or nine 

 years ago the sea broke its boundary, and flowed copiously 

 into the lake at every tide for a considerable time, by which 

 every species of fish were destroyed. 



The fish of Lough Neagh, in Ireland, called a Roach, is in 

 reality the Rucld, or Red-eye, Cyprinus erythropthalmus of 

 authors, to be hereafter described a fish belonging to the 

 second division of the genus Leuciscus of Klein, which has 

 the dorsal fin over the space between the ventral and anal 

 fins : the Roach has the dorsal fin more forward on the body, 

 and over the ventral fin, not over the space behind it. I 

 may here mention, that the representation of- the fish at the 

 bottom of the title-page of the third volume of Pennant's 



