Vol. 12. 1. Functional morphology of three bats: Eumops, Myotis, Macrotus. By Terry A. Vaughan. Pp. 1-153, 4 plates, 24 figures in text, July 8, 1959. 2. The ancestry of modern Amphibia: a review of the evidence. By Theodore H. Eaton, Jr. Pp. 155-180, 10 figures in text. July 10, 1959. 3. The baculum in microtine rodents. By Sydney Anderson. Pp. 181-218, 49 figures in text. February 19, 1960. 4. A new order of fishlike Amphibia from the Pennsylvanian of Kansas. By Theodore H. Eaton, Jr., and Peggy Lou Stewart. Pp. 217-240, 12 figures in text. May 2, 1960. More numbers will appear in volume 12. Vol. 13. 1. Five natural hybrid combinations in minnows (Cyprinidae). By Frank B. Cross and W. L. Minckley. Pp. 1-18. June 1, 1960. 2. A distributional study of the amphibians of the isthmus of Tehuantepec, México. By William E. Duellman. Pp. 19-72, pls. 1-8, 3 figs. August 16, 1960. 3. A new subspecies of the slider turtle (Pseudemys scripta) from Coahuila, México. By John M. Legler. Pp. 73-84, pis. 9-12, 3 figures in text. August 16, 1960. 4. Autecology of the Copperhead. By Henry S. Fitch. Pp. 85-288, pls. 13-20, 26 figures in text. November 30, 1960. 5. Occurrence of the Garter Snake, Thamnophis sirtalis, in the Great Plains and Rocky Mountains. By Henry S. Fitch and T. Paul Maslin. Pp. 289-308, 4 figures in text. February 10, 1961. 6. Fishes of the Wakarusa River in Kansas. By James E. Deacon and Artie L. Metcalf. Pp. 309-322, 1 figure in text. February 10, 1961. 7. Geographic variation in the North American Cyprinid Fish, Hybopsis gracilis. By Leonard J. Olund and Frank B. Cross. Pp. 323-348, pis. 21-24, 2 figures in text. February 10, 1961. 8. Descriptions of two species of frogs, Genus Ptychohyla--studies of American hylid frogs, V. By William E. Duellman. Pp. 349-357, pl. 25, 2 figures in text. April 27, 1961. 9. Fish populations, following a drought, in the Neosho and Marais des Cygnes rivers of Kansas. By James Everett Deacon. Pp. 359-427, pis. 26-30, 3 figs. in text. August 11, 1961. More numbers will appear in volume 13. Vol. 14. 1. Neotropical bats from western México. By Sydney Anderson. Pp. 1-8. October 24, 1960. 2. Geographic variation in the harvest mouse Reithrodontomys megalotis on the central Great Plains and in adjacent regions. By J. Knox Jones, Jr. and B. Mursaloglu. Pp. 9-27, 1 figure in text. July 24, 1961. 3. Mammals of Mesa Verde National Park, Colorado. By Sydney Anderson. Pp. 29-67, pls. 1-2, 3 figures in text. July 24, 1961. More numbers will appear in volume 14. Vol. 15. 1. The amphibians and reptiles of Michoacán, México. By William E. Duellman. Pp. 1-148, pls. 1-6, 11 figs. December 20, 1961.