Robert Adams, jr., 1846-1906
"Prof. G. N. Allen acted as botanist with great success, as far as Fort Ellis, and was assisted by Robert Adams. After Prof. Allen's departure, Mr. Adams took charge of the botanical collections." --F. V. Hayden 
"Robert Adams, a recent graduate in Classics from the University of Pennsylvania was named Allen's assistant." 
"Robert Adams wrote a series of letters to the Philadelphia Inquirer." 
- "University Archives Digital Image Collection," Robert Adams, Jr. (1849-1906) A.M. 1869, B.F. 1884, Portrait Photograph, section goes here, accessed February 12, 2013, http://dla.library.upenn.edu/dla/archives/detail.html?id=ARCHIVES_20020712001.
- F. V. Hayden, Preliminary Report of The United States Geological Survey of Montana and Portions of Adjacent Territories; Being A Fifth Annual Report of Progress (Washington: Government Printing Office, 1872), pg. 4.
- Merrill, Marlene. With Hayden in the Field : a Case Study Based on Unpublished Letters and Diaries from the 1871 Yellowstone Survey. 1993. Yellowstone Research Center Archives.