SMITHSONIAN EXPLORATIONS, KjjS 2^ 



After this somewhat hasty examination of the Wind River Range, 

 we crossed the Owl Creeks through the famous Wind River or 

 ThermopoHs Canyon into the Big Horn Basin. Two roads cross the 

 Big Horn Range, whose structure, hke that of the Wind River Range, 

 consists of a granite interior surrounded with sediiucntary rocks, 

 which, since the upHft, form a hand of varying width all the way 

 around the range. Several sections were studied along these roads. 

 In Tensleep Canyon, for instance, on the southern-most of these two 

 roads, new construction has exposed the softer Camhrian heds here 

 present, permitting their examination with ease. On the eastern side 

 of the range where this highway goes down again across the l)and of 

 sedimentary rocks, after having traversed many miles of the delightful 

 upland region with its open granite topography, the section is so 

 greatly disturbed as to be of little value except for checking observa- 

 tions made elsewhere along this front. We returned westward over 

 the Big Horns along the northern route, or the Dayton-Kane road, 

 getting the best exposure ])ossible in coming up the eastern side where 

 a new road was then under construction. Here a fine section and many 

 instructive fossils were obtained. It was found that where the road 

 drops down into the Big Horn Basin on the west, the section in Bald 

 Mountain and the adjacent hills was not as cleanly exposed as ex- 

 pected, and consequently also yielded but few fossils. Here again the 

 use of horses would have greatly enlarged the possible radius of 

 activity and perhaps would have made it possible to reach the more 

 fossiliferous beds reported to lie to the north in Sheep Mountain. 

 Nevertheless many stratigraphic data of importance were ol)tained. 



The latter part of the season was spent in the Teton Mountains, 

 particularly in Teton Canyon. Here, as in many places in this and 

 other ranges, the recent glaciation has steepened the slopes of the 

 canyons to such an extent that the softer shale l)eds are frequently 

 exposed on the slopes between the clift's which the limestones and 

 other massive rocks ususally form. In this place, almost directly under 

 the Grand Teton, the scenery is so magnificent that one is constantly 

 tempted to gaze upon it at the expense of considerable time. Indeed. 

 I think it safe to say that scarcely any other mountain group in the 

 world exceeds the magnificence of the Teton Mountains. 



The Wyoming ranges afford many fine examples of the varied 

 eft'ects of glaciation. In the Tetons, cirques and U-shaped valleys are 

 developed to text-book perfection, and in the Wind River Range, an 

 icefield more than 20 miles long still sends down its floods of milky 

 water. When a few warm days occur in succession in late July, melt- 



