Mr. W. Thompson on a neio British Fish. 269 



cilia bright silver, irides silvery, bounded by a blackish line 

 above and beneath. 



Although the expression of "common" be at variance with 

 what I could learn of the history of this species, it is probably 

 in allusion to it that Sir Wm. Jardine remarked in a letter to 

 me in November 1836, that he had heard of a fish called the 

 " freshwater herring" being common in Lough Derg. 



All the Coregoni hitherto recorded as British are lacustrine 

 species, thus rendering the addition to the Fauna of the pre- 

 sent one, which frequents the river Shannon, more than or- 

 dinarily interesting. That it migrates to the sea, as do others 

 of the genus, both in this and the western hemisphere, is by 

 no means improbable ; but as yet, instead of proof of the fact, 

 we have simply the conjecture of fishermen, who would not be 

 unlikely to draw such an inference from the mere circumstance 

 of capturing it at the same time with eels, which they know to 

 be on their migration seawards*. 



Salmo ferox, Jard. and Selby. — As in the instance of the 

 last species, I in announcing the Lake Trout to be found in Ire- 



* Coregonus PoUan, Thomp. A few observations on the pollan, the only 

 other species of Coregomis yet detected in Ireland, will not be out of place 

 here. When my paper on this fish was published (Mag. Zool. and Bot., 

 vol. i.) I had seen specimens only from Lough Neagh, but from Harris's 

 History of the County of Down it was quoted, *• that Lough Earn in tlie 

 county of Fermanagh has the same sort of fish, though not in so great plenty 

 [as L. Neagh]." This I am now enabled to verify. That the pollan is not 

 " in so great plenty " there, I became well satisfied during a visit — which 

 was indeed a very hurried one — to the lake in the autumn of 1837, when by 

 inquiry from maiiy persons I could not learn anything of such a fish. But 

 by the kind attention of Viscount Cole, who resides within a few miles of 

 Lough Erne, I have been lately favoured with examples of the C. PoUan from 

 that locality. On tiie 22nd of October last, I received a specimen which was 

 taken two days before, and was stated to have been the first caught this 

 season. On the 29th of the same month, 1 was obligingly supplied with 

 more examples; and in a letter dated from Florence Court the preceding day, 

 Lord Cole remarked, in reference to the species, " I have now procured in 

 all about ten or twelve. I cannot make out that they are ever caught in any 

 numbers in Lough Earn ; indeed they are never sought after — those which 

 I have got were taken in eel-nets in the upper lough. I have heai'd that 

 three or four were caught in the lower lough this year in a drag-net. This 

 is all I at present know about them." 



Since my account of the pollan appeared, I have been favoured by Dr. 

 Parnell with a specimen of the Coregonus of Loch Lomond (see his paper on 

 this subject in the Annals of Natural History, vol. i. p. 161.) and by Sir Wm. 

 Jardine with one of the Ullswater species ; both of which are distinct from 

 the Cor. Pollan, this having not as yet been found in any of the lakes of 

 Great Britain. 



