6 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1916. 



Second. The securing for the National Museum of a series of 

 geyser and hot spring deposits, also silicified wood from the petrified 

 forests and certain types of volcanic rocks. 



During the investigation and collecting, numerous photographs 

 were taken of geysers and hot springs and of deposits made from the 

 waters through evaporation and organic agencies. 



The collections were brought to the camps by pack horses and 

 buckboard and subsequently packed for shipment at Fort Yellow- 

 stone and Yellowstone. Material assistance was afforded by the co- 

 operation of the acting superintendent of the park. Col. L. M. Brett, 

 United States Army, and officers of the United States Engineer Corps 

 in charge of the maintenance and development of the park roads and 

 trails. 



Upward of 5 tons of specimens were collected and shipped to 

 the National Museum. This collection permits of the preparation of 

 a special Yellowstone Park exhibit of-great beauty and interest. 



It was found that algal growth was everywhere present when the 

 temperature of the waters was from 70° to not much above 180° F., 

 and that this growth had a marked effect upon the amount and charac- 

 ter of both calcareous and siliceous deposits. 



After completing the investigation of the geyser and hot spring 

 deposits, a trip was made to the Fossil Forest in the northeastern 

 section of the park, in the Lamar Eiver Valley. Large collections 

 were made here of silicified wood and various minerals, one of the 

 latter being a remarkable and beautiful form of calcite rosettes, 

 which were illustrated and technically described in the pamphlet on 

 Smithsonian explorations in 1915.^ 



The camp site in the Lamar Valley was one of unusual interest 

 and beauty. The high hills to the south showed the rock cliffs con- 

 taining silicified woods, calcite rosettes, and beautiful specimens of 

 chalcedony. A little way from the camp the party met with a 

 large herd of bison grazing freely in the broad open valley; also 

 herds of elk, bands of antelope, a few black bear, and an occasional 

 wolf. 



On leaving the park, after 675 miles of travel with the camp out- 

 fit, the party proceeded down the West Gallatin River Canyon, stop- 

 ping to examine the section of Cambrian rocks at the mouth of 

 Squaw Creek. The next permanent camp was made in Deep Creek 

 Canyon, 17 miles east of Townsend, Mont., where the extensive pre- 

 Cambrian sections of the Big Belt Mountains are beautifully shown. 

 About 2 tons of pre- Cambrian specimens were collected in this 

 vicinity before the storms of late September (1915) closed the sea- 

 son's field work. 



1 Smithsonian Miscellaneous Collections, Vol. 66, No. 3, 1916. 



