This classic manual provides a comprehensive guide to the identification and classification of common invertebrate animals, including mollusks, crustaceans, and worms. Drawing on decades of experience in the field, the author provides detailed descriptions of each species, as well as their behavior, habitat, and ecological significance. With its clear and concise format, this book is an invaluable resource for students, researchers, and anyone interested in the diversity of life in the natural world. This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work is in the "public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.