60 Book of the Black Bas& 



would begin to fade in a few hours, and in a few days or 

 weeks would become entirely changed in hue. 



The great lake trout {Cristivomer namaycitsh) exists in 

 three different states of color, according to situations in 

 which it is found, and were thought by the French hahi- 

 taiis of the great lakes to be three distinct fishes, known 

 as truite de greve, or trout of the muddy bottom; truite 

 des iattures, or trout of the rocky shores; and ti-uite du 

 large, or trout of the deep, open waters; the first being 

 dull-colored, the second bright and handsomely mottled, 

 and the last bluish and silvery. 



Charles Lanman truly observes, that the fish of streams 

 rushing rapidly over pebbly beds, are superior both in ap- 

 pearance and quality to those of ponds or semi-stagnant 

 brooks. But this may arise, not so much from any par- 

 ticular components of the waters themselves, as from the 

 fact that rapidly running and falling water is more highly 

 aerated, the atmosphere being more freely intermingled 

 with it, and therefore more conducive to the health and 

 condition of all that inhabit it. 



The influence of light in producing color in fishes is very 

 evident when we reflect that fishes are always colored upon 

 the back, which is exposed to the direct rays of light, and 

 pale 'underneath, usually being quite white on the abdo- 

 men. This fact is especially pronounced in the flat fishes, 

 which swim upon the side; thus the flounder, the sole, the 

 turbot, the halibut, etc., are dark and variously colored 

 upon the side presented to the light, while they are quite 

 pale or white on the under side. Fishes which inhabit 

 dark caves, owing to the absence of light, are entirely color- 

 less. 



That the age of fish has much to do with their color is 

 well known; a familiar example being the common gold- 



