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land and prairie, and numerous swamps 

 and marshes. Its upper course and many 

 of its upper tributaries lie in the region 

 once covered by glaciers, though now 

 traversed by great morains. Its fishes are 

 as diversified as the area it drains. • In its 

 mountain streams we find such fishes as 

 the trout, darters, minnows and suckers. 

 In the upland streams are darters, shin- 

 ers, suckers, sunfishes and small-mouth- 

 ed black bass. In the channels of the 

 larger tributaries are found the large 

 suckers, buffalo fishss, gar pike, channel 

 catfish, drum, pike and pickerel. The 

 lowland streams contain the dogfish, pi- 

 rate perch, some sunfishes, the large- 

 mouthed black bass, some suckers, 

 catfishes and other species. Min- 

 nows, darters, suckers and sun- 

 fishes are found in lowland, upland and 

 mountain streams, though not the same 

 species in each. These fishes belong to 

 families which are made up of many spe- 

 cies, some being strictly upland, 

 others strictly lowland, each having a 

 limited range. In the same way we have 

 fresh water fishes and salt water fishes; 

 some fishes, as the trout and salmon and 

 eel, live in both salt and fresh water. 

 Many other fishes, as the killifishes, 

 thrive best in brackish water. Each spe- 

 cies of fishes is best fitted for a particular 

 region into which it has been forced to 

 live, either to escape its enemies or to be 

 able to get a living easiest. In its migra- 

 tions it has moved along lines of least re- 

 sistance, and has colonized those streams 

 where Mother Nature has been able to 

 do the most for it. The darters are small, 

 perch-like fishes, which seldom exceed a 

 length of six inches, the average being 

 about three. All are active and swift 

 swimmers and well suited for a life 

 among the rocks and swift water of our 

 smaller streams. All countries have 

 small, swift, rocky streams, but few have 

 darters. In their stead we find loaches, 

 gobies, characins, sulpins, and the like. 

 These fishes have "become dwarfed and 

 concentrated, taking the place in their 

 respective habitats which the darters oc- 

 cupy in the waters of the Mississippi val- 

 ley. By the same process of 'analogous 

 variation' the cichlids of South America 

 parallel the sunfishes of the United 



States, although in structure and in ori- 

 gin the two groups are diverse." 



Dr. Jordan tells us that the trout of the 

 Pacific coast came to America from 

 Asia, and gradually spread eastward and 

 southward until now it is found in all the 

 streams of the Rocky Mountains, the 

 Sierra Nevada, the Cascades and the 

 Coast range. It is but a short distance 

 from Kamchatka to Alaska, and this dis- 

 tance is traveled by trout to this day; 

 once over, a fish able to spend much of its 

 time in salt water could easily colonize 

 all our coast streams. Whether or not all 

 of our Pacific trout are descendants of 

 one species, the cut-throat trout, is more 

 or less uncertain, though it is quite cer- 

 tain that all have descended from not 

 more than two or three species. In many 

 places they have been able to pass from 

 the head waters of one river to that of 

 another, just as they now pass from the 

 head waters of the Columbia to the Mis- 

 souri by the way of Two Ocean Pass. 

 The ancient lakes, Lahontan and Bonne- 

 ville, no doubt assisted them in their mi- 

 grations. Since these have disappeared 

 each colony has had to remain more or 

 less isolated. In time they have become 

 somewhat changed, to better adapt them- 

 selves to their new environment. These 

 changes have developed certain peculiar 

 characters, by means of which we 

 can distinguish one kind of trout from 

 another, just as the farmer distinguishes 

 his Berkshire from his Poland China. 

 Spread, as the trout are, over such a large 

 area, in such an immense variety of 

 streams and lakes, and with a vertical 

 ranee of over one thousand feet, we 

 would certainly expect as large a number 

 of species and varieties of trout to be de- 

 veloped as we find at present in the 

 streams of our west coast. 



Fishes are found in the deepest parts 

 of the ocean. Some of these are peculiar 

 to the deep waters, none of the shore 

 fishes resembling them. On the other 

 hand, many deep sea fishes belong to 

 families well represented in the shallow 

 water. The flounders are found in water 

 at all depths, and the same is true of the 

 bat fishes, rock fishes and other shore 

 fishes. It is easy to understand how 

 these fishes have found their way to the 



