Washington DC: Government Printing Office, 1915. Illustrated. Hardcover. 199pp. Quarto [29.5 cm] Bound in sturdy black cloth with a gilt stamped title on the spine. Very good. Ex-library. There is a glossy sheen over the library classification notation at the foot of the spine. There is a library label on the front pastedown. The front free endsheet is absent. The title page has a perforated library stamp and a small numerical stamp. There are a few perforated library stamps in the text. Item #25659
Subjects include Formations Constituting the Montana Group and Stratigraphic Position and Age of the Judith River Formation.