Nature

A Short History of the Academy of Natural Sciences of Philadelphia

From North Pole to Equator: Studies of Wild Life and Scenes in Many Lands

On poetic interpretation of nature

Second State of the Union Address

Natural History: Mollusca

Natural History: Fishes

Devils Tower National Monument

Masters of the Wilderness

Birds of Song and Story

The Stewardship of the Soil

Tales of a Vanishing River

Mushroom and Toadstools

Four-Footed Americans and Their Kin

John Kerry's testimony before the Senate Foreign Relations Committee

Elementary Botany

Lectures on Landscape

Two Ways of Becoming a Hunter

At the Sign of the Fox

The Catalpa Expedition

Oxford