474 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
The principal tributaries from the east are the Eio Gila (draining 68,023 square 
miles) and the Little Colorado or Colorado Chiquito (draining 29,268 square miles), in 
Arizona; the San Juan in New Mexico, Colorado, and Utah (draining 26,472 square 
miles); the Grand, White, and Yampa in Colorado, aiid the Big Sandy Eiver in 
Wyoming. The streams from the west are few and rather small, the Duchesne, 
Price, andVirgen being the only ones of any importance. The tributaries from Colo- 
rado are all clear, cold, mountain streams well suited to trout; the headwaters of Green 
Elver are similar in character; while the tributaries from Utah, Eevada, California, 
and Arizona are from comparatively arid regions. During time of rains these streams 
become of considerable size and are very turbid from the easily eroded country through 
which they flow. They decrease in size as readily, and in some cases disappear in the 
sand. Such streams are of course uusuited to a large variety of fish life. 
While the headwaters of the Colorado are ordinarily clear and pure, the lower 
Colorado is one of the muddiest rivers in America and is unfit for any but mud-loving 
species. As already pointed out by Dr. Jordan,* the headwaters are well supidied 
with trout, accompanied by Agosia yarrou'i and the blob (Coitus hairdi ])iinctiilatus). 
Lower down appear four species of suckers [Xyrauclien cyplio, X. tincompaligre^ Catosto- 
mus iatijnnnis, and Pantosteiis delpliimis), and with them the round-tail (Gila.rohusta), 
the ‘Gvhite salmon” {Ptychocheilus hicius), and Williamson’s whitefish (Coregonus 
■loilliamsoni). Still lower down are found the bony-tail (Gila elegans) and other species 
of Catostomus, while in the Arizona region and the other arid i>ortions are found the 
peculiar genera Lepidomeda, Meda, and Plagopterus. 
Very little collecting has been done in the Colorado Basin, the following being a 
list of all the collections, or at least all those which have been reported ui^on and the 
literature of which is accessible to us: 
1. Three nominal species collected by Dr. S. W. Woodhouse, naturalist to Capt. 
Sitgreaves’s expedition, 1852. These were described by Baird & Girard in 1853. 
2. Eighteen nominal species collected by the naturalists of the Pacific Eailroad 
Survey and of the United States and Mexican Boundary Survey (John H. Clark, John 
L. Le Conte, Arthur Schott, Dr. C. B. Kennerly, and Dr. A. L. Heermann). These 
constituted the first considerable collections, and were described by Baird & Girard, 
or Girard alone, in 1853-56. 
3. Thirteen nominal species obtained by Campbell Carrington, naturalist to the 
Hayden surveys of 1870 and 1871. These collections were studied and reported upon 
by Prof. Cope, in 1871 and 1872. 
4. Twenty-seven nominal species collected by the various naturalists of the 
Wheeler Survey (Cope, Yarrow, Heushaw, Eewberry, lOett, Eothrock, Butter, Loew, 
Bischoff, and Birnie) in 1871-74. These are by far the most extensive collections 
wdiich have as yet been made in this region, and formed the basis for the admirable 
report by Cope & Yarrow in volume 5 of the Wheeler Eeports and for Prof. Cope’s 
valuable paper on the Plagopterime and the Ichthyology of Utah, in 1874. 
5. One species (Xyrauchen cyplio) obtained at the mouth of the Gila, and described 
by Mr. William E. Lockiugton in 1880. 
6. Seven nominal species collected at Fort Thomas, Ariz., by Lieut. W. L. Car- 
j>euter, U. S. A. These were reported upon by Philip H. Kirsch in 1889. 
U. S. FisL Commission, ix, 1889 (1891), 22. 
