1951. 207 pp. Paperback in good condition. Philadelphia: Transactions of the American Philosophical Society, New Series, Volume 41, Part 3, pp. 385-591. Original wrappers, with heavy wear. Water wrinkle throughout the pages, and the spine is significantly worn, but the text is still readable and no pages are stuck together or ripped. Association copy: Mary Clench, president of the Wilson Ornithological Society.