622 FOURTH RKPORT — 18.34. 



in establishing tlie differences of species are quite insufficient, 

 and the comparative examination of these pseudo-species admits 

 of vei'y different results. 



M. Agassiz is convinced that all the fish belonging to this 

 family on the Continent may be reduced to the six following- 

 species : 



1. Salmo Umhla, Linn.; the Char oi England; \\\e Omhre 

 Chevalier of the Lake of Geneva ; the Rotheli of Swiss 

 Germany ; and the Schwarz Reutel of Saltzburg. 



Synonyms : Salmo Salvelinus , Linn. ; Salmo alpinus, 

 Linn. ; Salmo salm,arimis, Linn,, (but not the Salmo 

 alpinus of Bloch). 

 This fish is found in England and Ireland, in Sweden and 

 Switzerland, and in all the southern parts of Germany. 



2. The Salmo Fario, Linn. ; the Trout of brooks ; Common- 

 Trout, Gillaroo-Trovt, and Parr. 



Synonyms : Salmo sylvaticus, Schrank ; Salmo alpinus, 

 Bloch ; Salmo punctatus, Cuvier ; Salmo marmora- 

 tus, Cuvier ; Salmo Erythrimis, Linn. 

 It is found as extensively as the first species. 



3. Salmo Trutta, Linn. ; Sea-trout, Salmon-trout. It is 

 the same as the Salmo Lemanus of Cuvier, and the Salmo 

 albus of Rorideletius. 



4. Salmo lacustris, Linn. The same as the Salmo Illanca 

 and the Salmo Schiffermulleri of Bloch. 



Found in the lakes of Lower Austria, and in the Rhine above 

 Constance. 



5. Salmo Salar, Linn. ; the True Sabnon. The Salmo 

 hamatus of Cuvier is the old fish, and the Salmo Gadeni 

 of Bloch the young fish. 



Foutid in the northern seas, whence it ascends the rivers 

 even as far as the Swiss lakes. 



6. Salmo Hucho, Linn. 



Peculiar to the waters of the Danube. 



It results, then, from these observations, that the different 

 species of the Salmon family, far from being confined within 

 the narrow limits of some small bodies of fresh water, are, on 

 the contrary, very widely distributed. They also thrive in all 

 climates, at least in all elevations above the surface of the 

 ocean, whether in fresh water or in salt. Nevertheless they 

 prefer those situations where the water is limpid. 



The author concludes by stating that it is not upon vague 

 data that he has drawn these several conclusions, but upon the 



