Twelfth Annual Report of the United States Geological and Geographical Survey of the Territories: A report of progress of the exploration in Wyoming and Idaho for the year 1878, Part I: Geology, paleontology, and zoology

This report includes the labors of the corps for the field season of 1878, and the office work until the close of the existence of the Survey by law June 30, 1879. Several of the members have, however, performed very important work since that time in elaborating their individual reports, which has added greatly to their interest and value.

A general summary of the work for the season of 1878 will be appropriate in this connection. Owing to the length of the session, Congress did not pass the usual appropriation for the work of the Survey until July, and consequently the period for work in the field was comparatively short.

The headquarters of the Survey was at Cheyenne, Wyo., the same as the preceding season. Four parties were organized, but in such a manner that in case of necessity they could be divided for special duty. All our outfit and animals were transported from Cheyenne to Point of Rocks and Green River Stations on the Union Pacific Railroad, and from thence the parties pursued their way northward to their respective fields of labor.