This is an OCR edition without illustrations or index. It may have numerous typos or missing text. However, purchasers can download a free scanned copy of the original rare book from GeneralBooksClub.com. You can also preview excerpts from the book there. Purchasers are also entitled to a free trial membership in the General Books Club where they can select from more than a million books without charge. Original Published by: W. Wood in 1912 in 321 pages; Subjects: Heredity; Evolution; Science / Life Sciences / Biology / General; Science / Life Sciences / Evolution; Science / Life Sciences / Genetics & Genomics;