_Nature and Science on the Pacific Coast_
Wild Animals at Home _E. T. Seton_
Our National Parks _John Muir_
Western Wild Flowers _Margaret Armstrong_
Flora of Colorado _Rydberg_
Mountain Wild Flowers of America _Julia Henshaw_
Rocky Mountain Wild Flowers _Clements_
Handbook of Birds of Western United
States _Florence Merriam Bailey_
Wild Animals at Home _E. T. Seton_
The Mammals of Colorado _Warren_
The Adventures of James C. Adams _Hittel_
In Beaver World _Mills_
Manual of the Trees of North America _Sargent_
Field-Days in California _Torrey_
Trees of California _Jepson_
Three Wonderlands of the American West _Thomas D. Murphy_