REPORT OF COMMISSIONER OF FISH AND FISHERIES. CXV 



both years, and contains descriptions of the principal features, physi- 

 cal and biological, of each of the basins studied by him, namely, the 

 Snake Kiver system, Yellowstone Eiver system, Gardiner Eiver sys- 

 tem, Madison Eiver system, and Flathead Eiver system. Many of 

 the organisms obtained are also described in detail. 



As no topographical surveys have been made about Flathead Lake, 

 its outlines and dimensions are still matters of conjecture, but it is said 

 to be about 24 miles long and from 12 to 17 miles wide. Its principal 

 characteristics, as compared with those of Yellowstone Lake, are thus 

 described by Prof. Forbes: 



Although this lake stands in some respects in tlecidecl contrast to Yellowstone 

 Lake, these differences tend largely to neutralize each other. Flathead Lake is over 

 200 miles farther northward than Yellowstone, but the latter is 4,775 feet the higher 

 above the level of the sea. These lakes lie on opposite continental slopes, their 

 waters passing respectively into the Gulf of Mexico and the Pacific Ocean, but neither 

 is more than a few miles from the relatively low continental divide, easily passable 

 by most of the plant and animal forms likely to occur in such waters. Both lakes 

 lie in the c(furse of streams of considerable size, but these streams flow in opposite 

 directions, the inlet of Flathead Lake coming southward from the British possessions, 

 and its outlet running first to the south and then to th« west as Flathead River, a 

 branch of the Columbia,, while Yellowstone River, rising about 150 miles from the 

 lake, runs northward more than a degree below it before swinging to the east to join 

 the Missouri. Nevertheless, the headwaters of the two river systems interlace almost 

 inextricably through interlocking mountain valleys along several hundred miles of 

 the main Rocky Mountain range. Both lakes lie among the mountains, from whose 

 rugged gulches the snow never wholly disappears, and both are bordered by forest 

 broken by park-like openings on the lower slopes ; but the geological structure of the 

 surrounding country and the chemical composition of the rocks which form their 

 shores and beds difi'er widely for the two, and the forests, all pine and fir and other 

 conifers around Yellowstone Lake, are largely deciduous trees about Flathead. 



The lakes are similar in size and are both deep enough to give a deep-water char- 

 acter to their interior fauna, but Flathead has much the more uniform shore line and 

 contains — if I may judge from the parts of it which we examined — a larger extent 

 of shallow and weedy water. It is divided, in fact, by a chain of islands stretching 

 across its lower third, into unlike parts, the northern deep and clear, and the south- 

 ern shallow and easily stirred up to its clayey bottom by the winds. * * * The 

 principal tributaries are the Flatliead, a still, broad river, larger than the Yellow- 

 stone at the lake, running from Demersville, most of the way between flat, low 

 banks ; the Big Fork or Swan River, a rocky stream, whose course from Swan Lake 

 to the Flathead is an oft-repeated alternation of wild rapids and comparatively 

 qniet reaches ; and Dayton Creek on the west, which I did not see. The outlet (Flat- 

 head River) flows rapidly away from the lake between bluff"y blanks which presently 

 become a canyon. 



TEXAS. 



The act of Congress relative to investigations in the Eocky Mountain 

 region also provided for similar inquiries with respect to the Gulf 

 States. As the appropriation made for this purpose did not permit of 

 extensive explorations, they were limited to the State of Texas, where 

 it was expected a convenient location would be found to meet the 

 requirements of a wide territory which has hitherto derived compara- 

 tively few benefits from the fish-cultural operations of the Government. 

 The field work was conducted during November and the early part of 



