Environmental Protection

The Geology of Groton State Forest

The Migration of North American Birds

Krag and Johnny Bear

Wild Earth

The book of earth

The Strangest Things in the World: A Book About Extraordinary Manifestations of Nature

Forest, Lake and Prairie

Wilderness Honey

The Wisdom of Albert Schweitzer

Adventure Travel Unleashed

The Gospel According to the Earth

Sketches in Duneland

Thornton Burgess: Collected Works

How to Camp Out

The Wild Elephant and the Method of Capturing and Taming it in Ceylon

The Rocky Mountain Wonderland

A Pictorial Guide to Mesa Verde National Park

Mooswa & Others of the Boundaries

Pearls and Pebbles; or, Notes of an Old Naturalist

Islands and Communities