THE TALE OF THE FISHES 



follow the genealogical tree, you are to remember that 

 two tendencies inhere in all fishes, viz: the one, to re- 

 main loyal to the specific tribal form; the other, to 

 diverge from the original type in efforts at adaptation 

 to new conditions of existence. Recent fishes have 

 diverged only in minor details from their ancestral 

 stems, because their aquatic environment has retained 

 its general characteristics. Hence the evolution of our 

 fish fauna implies ages of time. 



Plate 3 represents the Lake Sunapee saibling, the 

 upper specimen in summer uniform as I first beheld it 

 in 1882, the lower in the paint of autumn. You will 

 remark the absence of aureole in all the American and 

 foreign specimens of the Alpine charr I shall show you. 

 To get the spot effect, you seem to be looking through 

 holes in a dark veil of mist to catch the nuptial tones 

 beneath. Note the shape of tail, the large fins, and 

 the entire lack of mottling on the back. 



The Blue Back of Maine (Picture No. 4) is 

 plainly a congeneric form. Like the Windermere 

 charr, it enters streams to spawn, thus affecting a habit 

 of the brook trout. Unlike its Sunapee relative, which 

 is extremely sensitive, especially to changes of water, 



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