TRANSACTIONS OF THE SECTIONS. 621 



mine the various species which are found in the fresh waters 

 of the Continent, grounding his examination upon the study of 

 the intei'ior organization and upon the particulars already de- 

 termined which the integuments present concerning the struc- 

 ture of the scales. He has also introduced the shape of the 

 body and the proportional size of its internal parts as important 

 accessories to the description of the species. Of these in- 

 vestigations he proposes to give an account in his treatise upon 

 the fishes of the fresh waters of Central Europe, confining him- 

 self here to a short statement of the results which he has ob- 

 tained. 



It is a very singular fact that those fishes which are the most 

 widely distributed, and those which are most highly prized, 

 are precisely those whose natural history is the most perplexed. 

 The opinions, too, which are most general concerning their 

 geographical distribution are not at all in unison with the real 

 state of things. There scarcely exists a country to which some 

 peculiar species of salmon has not been assigned ; and the 

 author adds that even in the Re gne Animal o^ Cuvier are many 

 nominal species, which are not even local varieties, as he pur- 

 poses ere long to demonstrate. 



The cupidity of the fisherman, the rivalry of epicures, and 

 the fastidiousness of the palate of salmon-eaters, have, without 

 doubt, contributed to spread these opinions upon the narrow 

 limit assigned to the haunts of the species of the salmon. There 

 is especially a famous vai-iety in the annals of epicurism, over 

 which the greatest possible obscurity has been cast, it is the 

 Ombre Chevalier, the Char, or Alpine Trout. ■ 



After having attentively examined the Continental varieties, 

 M. Agassiz with eagerness availed himself of the opportunity 

 lately afforded him of examining near their native haunts seve- 

 ral species of this genus which are found in England. Through 

 the kindness of Sir William Jardine and of Mr. Selby, he has 

 also had an opportunity of examining all those which they have 

 collected from the Scottish lakes ; and the result has been that 

 he has succeeded in determining the perfect identity of many 

 of them with the species found in other countries in Europe, 

 while, on the other hand, he is convinced by the observations of 

 these naturalists that there are species peculiar to Scotland. 

 Nevertheless it is true that systematic authors, from having 

 allowed themselves to fall into error through the prevailing opi- 

 nions circulated concerning the vast multitude of species of this 

 genus, have been investigating the characters of a great num- 

 ber of merely imaginary species. But to the philosophical 

 naturalist the distinctions upon which they support themselves 



