Fossils

Links With the Past in the Plant World

The Coal Measures Amphibia of North America

The Frozen North

The Coal Measures Amphibia of North America

Life's Dawn on Earth

Fossils: A Story of the Rocks and Their Record of Prehistoric Life Denver Museum of Natural History, Popular Series No. 3

The Black Moose in Pennsylvania

Evolution

Dinosaurs, with Special Reference to the American Museum Collections

Animals of the Past

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

Cave Hunting

The Lost Lemuria

Pleistocene Bats from San Josecito Cave, Nuevo Leon, Mexico

Voyager 1 Encounters Saturn

The Survival Handbook