Letter from Ralph H. Cameron to Carl Hayden thanking him for forwarding Senate Bill No. 390 with the report of March 31st, 1918, and expressing interest in their upcoming meeting in Washington.

Letter from Ralph H. Cameron to Carl Hayden requesting a delay on the introduction of the Grand Canyon bill until he can meet with himself and Senator Ashurst in Washington.

Letter from Ralph H. Cameron asking to speak to Carl Hayden concerning a matter relevant to the bill granting National Park status to the Grand Canyon.

Handwritten cover titled, "Nature Notes of Grand Canyon, Polyphemus Moth, Female, Found at Grand Canyon, 5 July 1928, Vol. 3 - No. 2." Cover includes a drawing of the moth.

Typescript report, black and white, describing the birds of Grand Canyon National Park with cover drawing of a bald eagle.

Typescript report, black and white, describing the mammals of Grand Canyon National Park with cover drawing of a bighorn sheep.