42 AMERICAN FISHES. 



consequences, to disregard, and even to hold in contempt, the teach- 

 ings of scientific men, as mere theoretical dreamers, useless coiners 

 of hard terms, and founders of distinctions, founded upon no difference. 



Such, I am sorry to say, is too often the habit of sportsmen ; who 

 will frequently give ear to the superstitious and absurd garrulity of 

 some rustic ignoramus, who pronounces his absolute yea or nay upon 

 some fact about which he is utterly ignorant, and who has no earthly 

 qualification for judging on the qualities of the bird, beast, or fish in 

 question, t-ian that of having seen it so often that he ought to know 

 something about it, which he does not ; while they turn away contemp- 

 tuously, or listen coldly to the teachings of the man, whose arguments 

 are founded upon facts that cannot err, upon deductions drawn from 

 differences of anatomical structure, permanent from generation to gene- 

 ration, and liable to no modification by the change of external circum- 

 stances. 



This it is which renders the structure of the fins, the shape of the 

 gills, the system of the teeth, and other matters of the same kind, 

 which pass wholly unnoticed by the clod-hopping hunter, of all import- 

 ance in distinguishing one species from another ; while the size, the 

 weight, the color and number of the spots, things to which he will 

 point as decisive with all the pig-headed presumption of self-conceited 

 ignorance, are of little, if any weight, as varying in individuals, and 

 not transmitted, like to like, through generations. 



Almost all the really distinct species of the Salmonidce are distin- 

 guished principally one from another by the form of the head and the 

 structure of the gills in the first degree, and by the dental system in 

 the second. Any permanent and unvarying difference in these, 

 coupled to other variations of color, form, habit, or the like, which 

 might otherwise be deemed casual, being held sufficient to constitute 

 a distinct species. 



Many discoveries have been made through these means of late years; 

 many varieties, which were formerly supposed to be truly distinct, 

 having been proved to be identical ; and many new species discovered 

 — the tendency of the whole having been to simplify, and to diminish 

 the number of species, in the upshot, and thereby to decrease ths 

 labors of the student, and to facilitate the acquisition of science. 



