486 NATURAL HISTORY OF AQUATIC ANIMALS. 



are land-locked. Certain modifications of structure have resulted from access to nutritious food 

 in almost unlimited quantity and from existence for many generations in extensive bodies of water. 



SIZE. The most striking of these is the greater size. It sometimes attains the weight of 

 one hundred and twenty pounds, while our common Char, Salvelinus fontinalls, even under 

 similar conditions, never exceeds fourteen or fifteen. This is due, perhaps, to the greater ease 

 with which, for hundreds of generations, the Lake Trout have obtained their food. They are 

 almost always found in the same lakes with one or more kinds of white-fish, whose slow, helpless 

 movements render them an easy prey, and upon whose tender, luscious flesh the Lake Trout 

 feeds voraciously. From abundant food and slight exertion results bulk of body. This becomes 

 hereditary. Even the eggs in time are larger, just as in the Land-locked Salmon they are smaller, 

 than in the parent species, and the young fish begins its career with an advantage. As the 

 nascent species gains in magnitude the scales, always small like those of the Char, increase 

 iu number, that the growing body may be covered. In like manner an additional ray or two may 

 be developed to re-enforce the dozen supporters of the dorsal fin. The change iu dentition is a 

 result of the change of habits. Feeding upon large, strong-scaled fish, instead of insects and min- 

 nows, natural selection provides the Lake Trout with more and stronger teeth. It would perhaps 

 seem like a hasty generalization to point to Salvelinus fontinalis as the form from which the Lake 

 Trout has been developed, but one may fairly take into consideration the fact that this species 

 alone, of all the Salmo group, is usually associated with the fish under consideration, occupying the 

 streams which flow into the lakes of Northeastern America, and frequently entering these lakes. 

 That 8. fontinalis, even when retaining its predilection for the streamlets, shows a tendency to 

 extraordinary growth when ample waters, like the lakes of Maine or the lower stretches of the 

 Nepigon, are accessible, is also known. 



VARIATIONS. The Brook Trout shares with the Lake Trout its tendency to variations in size, 

 shape, and color. Every lake of Northern New York and New England has its own variety, which 

 the local angler stoutly maintains to be a different species from that found in the next township. 

 Some are as black as a tautog, some brown with crimson spots, some gray, with delicate reticula- 

 tions like those of a pickerel. The usual type to be found in the Great Lakes is brown or gray, 

 dappled with lighter shades of the same general tint. Naturalists have been sadly misled by their 

 Protean modifications. The "Namaycush" of the North, the "Togue" or "Tuladi" of the Maine 

 and New Brunswick Indians and lumbermen, the "Siscowet" or "Siskawitz" of Lake Superior, 

 the "Trout" of Winnipiseogee, and that of the Adirondack lakes, have each been honored with a 

 distinct binomial. 



The angling authorities still refuse to admit that the Lake Trout of the East is identical with 

 the Mackinaw Trout, or Namaycush, supporting their views by accounts of their very different 

 habits. A careful study of the dead fish is sufficient, however, to convince a trained observer that 

 there are no structural characters by which these different forms may be separated into species. 

 The local variations should undoubtedly be taken into consideration, and when these are better 

 understood it is probable that zoologists and anglers will compromise by agreeing to consider the 

 most strongly marked types as races, or breeds, such as are now recognized among dogs, pigeons, 

 and other domesticated animals. Having never seen the fish called the "Siscowet," Salvelinus 

 siscowet, I cannot express an opinion as to its distinctness from the Mackinaw Trout, but good 

 ichthyologists assure me that its peculiarities are very slight, consisting chiefly in the smaller head- 

 teeth, and fins, and the stouter body. Since, however, it is always distinguished from the Namay- 

 cush by the Indians and fishermen of Lake Superior, who often see them side by side, it seems 

 probable that it may claim at least sub-specific rank. The matter of laud-locking is one which 



