GENERAL DESCBIPTION OF REGION. 9 



the next day Mr. Hudson, Mr. Nowlin, and I left Cheyenne for Jackson 

 Hole, via Pocatello and St. Anthony, Idaho. To reach the scene of 

 our work, a two days' stage trip after leaving the railroad was neces- 

 sary. We left St. Anthony on March 15 and passed the night at 

 Victor, Idaho, close to the western base of the lofty and picturesque 

 Teton Eange. Next day we crossed this range, over from 10 to 40 

 feet of snow, via the Teton Pass, at 8,429 feet altitude, and descending 

 the eastern slope of the range crossed Snake River and reached the 

 town of Jackson. This point, in the southern part of Jackson Hole, 

 was our headquarters for nearly three months. From here we made 

 trips by stage and other conveyances and on foot to various parts of 

 the valley of Snake River from the head of Jackson Lake south nearly 

 to Hoback River and visited also the valleys of Buffalo and Gros 

 Ventre Rivers. We left the valley in early June to take up other 

 work, but Mr. Nowlin returned about August 1 and continued the 

 investigations. 



During the progress of the work I was greatly assisted by Mr. 

 Nowlin. His intimate personal acquaintance with the people of the 

 region and with the various phases of the problem made him peculiarly 

 valuable. To the residents of the region, also, I am greatly indebted 

 for courtesies extended. 



GENERAL DESCRIPTION OF THE REGION. 



Jackson Hole is the name commonly applied to that part of the 

 Snake River Valley between Jackson Lake and the mouth of Hoback 

 or Fall River. (See map, PI. III.) It is a basin about 40 miles in 

 length from north to south and averaging about 15 miles in width 

 and extends in a north-northeast and south-southwest direction. It 

 has an altitude of about 6,700 feet at its north end and falls to about 

 6,000 feet at its southern extremity. Snake River, after issuing from 

 Jackson Lake, traverses the valley in a direction slightly nearer 

 southwesterly than the general trend of the basin, entering it at its 

 northeastern extremity and crossing to its western border in the course 

 of a few miles. This river has a rather uniformly rapid current and is 

 moderately direct in its course, but in places divides into numerous 

 channels inclosing large islands. From the east it receives succes- 

 sively Pacific Creek (whose twin, Atlantic Creek, heading in the same 

 meadow, is tributary to the Missouri), Buffalo River or Buffalo Fork, 

 Gros Ventre River, and Little Gros Ventre or Flat Creek. Parts of 

 Snake River and its larger tributaries are bordered by groves of 

 narrow-leaf cottonwoods (Populus angustifolia) , interspersed with a 

 few spruces, with an undergrowth of dogwood, alder, and other 

 shrubs. Along some of the tributaries of Snake River are natural 

 marshy meadows which support a rank growth of marsh grasses, with 

 thickets of willows on their borders and along the streams, and a 

 15973°— Bull. 40—11 2 



