Published in 1922, this groundbreaking work in the field of biogeography offers a new perspective on the origins and distribution of species around the world. Author J.C. Willis argues that there is a close relationship between the age of a particular area and the number and diversity of species found there. Filled with detailed maps and charts, this book remains an essential work for anyone interested in the science of evolution and 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.