Bibliographical Notices. 291 



the smaller alpine streams. On tab. Ill b. are given representations of 

 the head of a deformed Trout, similar to that represented by Mr. 

 Yarrell, and which we know to occur in several lochs in Wales and in 

 Scotland, and to be not uncommon in the localities where it is found. 

 The malformation is extremely uniform or similar in all the specimens 

 or representations of it which we have seen, but the cause has not yet 

 been noticed, nor has it been attempted to be accounted for. Is the 

 race continued by breeding ? 



Seven plates illustrate two species of migratory Trout which are 

 given under the names of S. trutta and lacustris Linn.*. In these we 

 think we recognise the two British fishes which have been confounded 

 under the provincial name of "Sea Trout." They are very distinct 

 in some of their states, and the form of the tail distinguishes them, 

 together with the colours during the breeding season, but we should 

 have preferred to have seen figures of these species when in high 

 condition ; residence in a lake may in various ways influence the form. 

 The young of these fish constitutes the S. albus of Fleming. Should 

 the S. trutta of this work not stand as S. eriox of Willughb. 1 



The Char are all placed under S. umbla, Linn., and the " Welsh Char" 

 is given as an English synonym. Although we know the Char to vary 

 very considerably, we are inclined to refer the British fish to two 

 species, chiefly distinguished by the great difference in the scaling. 

 Those figured by M. Agassiz seem all referable to the " Northern 

 Char" of modern British writers. 



S. hucho of the Danube, unknown in the British waters, is represented 

 in the young and adult states, and the last plates delineate the Thymal- 

 lus vexillifer, Agass., or Common Grayling, found only by the Bri- 

 tish ichthyologist in certain districts in England. 



In looking at the list of the Salmon of Britain and Central Europe 

 comparatively, we are prepared for a close resemblance of species ; 

 but from the work before us we perceive one species, S. hucho of the 

 Danube, which does not occur in Britain or Ireland, while we find 

 omitted the Bull Trout of the river Tweed, (the S. eriox of some authors, 

 but not of Willughby,) and the great Trout of the Scotch, Irish, and 

 North of England lakes. These we have no doubt in being distinct 

 species, and it appears to us remarkable that the latter should be want- 

 ing to the Swiss lakes. Among the common Trout, S. fario, we feel 

 inclined to adopt more species than those of the Swiss ichthyologist, but 

 as the specimens now figured are chiefly river varieties, and certainly 

 all one species, we are not so able to judge how the varieties in the lakes 



* We are presuming that the S. lacustris here given is a migratory species, and if so we think 

 the name objectionable. 



2 Q 



