Fossils

The Black Moose in Pennsylvania

Evolution

The Radio Boys with the Forest Rangers; Or, The great fire on Spruce Mountain

The Romance of Modern Geology

The Adventures of a Grain of Dust

Thoughts on a Pebble, or, A First Lesson in Geology

Essay on the Theory of the Earth

The Ultimate Rockhounding Handbook

Cambrian Ocean World

The Common Rocks and Minerals of Missouri

Texas Rocks and Minerals: An Amateur's Guide

Fossil Forests of the Yellowstone National Park

The Geologic Setting of the John Day Country: Grant County, Oregon

The Pleistocene of North America and its vertebrated animals

The Flow of Time in the Connecticut Valley: Geological Imprints

African Dinosaurs Unearthed

Bernissart Dinosaurs and Early Cretaceous Terrestrial Ecosystems

The Desert Bones

A Short History of the Academy of Natural Sciences of Philadelphia

The Ornithosauria