18. The mammals of Wyoming. By Charles A. Long. Pp. 493-758, 82 figs. July 6, 1965, $3.00. Index. Pp. 759-784. (Continued on outside of back cover) (Continued from inside back cover) Vol. 15. 1. The amphibians and reptiles of Michoacan, Mexico. By William E. Duellman Pp. 1-148, pls. 1-6, 11 figures in text. December 20, 1961. $1.50. 2. Some reptiles and amphibians from Korea. By Robert G. Webb, J. Knox Jones Jr., and George W. Byers: Pp. 149-173. January 31, 1962. 3. A new species of frog (genus Tomodactylus), from western Mexico. By Robert G. Webb. Pp. 175-181, 1 figure in text. March 7, 1962. 4. Type specimens of amphibians and reptiles in the Museum of Natural History, The University of Kansas. By William E. Duellman and Barbara Berg. Pp. 188-204. October 26, 1962. 5. Amphibians and reptiles of the rainforests of southern El Peten, Guatemala. By William E. Duellman. Pp. 205-249, pls. 7-10, 6 figures in text. October 4, 1963. 6. A revision of snakes of the genus Conophis (Family Colubridae, from Middle America). By John Wellman. Pp. 251-295, 9 figures in text October 4, 1963. 7. A review of the Middle American tree frogs of the genus Ptychohyla. By William E. Duellman. Pp. 297-349, pls. 11-18, 7 figures in text. October 18, 1963. 50 cents. *8. Natural history of the racer Coluber constrictor. By Henry S. Fitch. Pp. 351-468, pls. 19-22, 20 figures in text. December 30, 1963. $1.00. 9. A review of the frogs of the Hyla bistincta group. By William E. Duellman. Pp. 469-491, 4 figures in text. March 2, 1964. 10. An ecological study of the garter snake, Thamnophis sirtalis. By Henry S. Fitch. Pp. 493-564, pls. 23-25, 14 figures in text. May 17, 1965. 11. Breeding cycle in the ground skink, Lygosoma laterale. By Henry S. Fitch and Harry W. Greene. Pp. 565-575, 3 figures in text. May 17, 1965. 12. Amphibians and reptiles from the Yucatan Peninsula, Mexico. By William E. Duellman. Pp. 577-614, 1 figure in text. June 22, 1965. 13. A new species of turtle, genus Kinosternon, from Central America. By John M. Legler. Pp. 615-625, pls. 26-28, 2 figures in text. July 20, 1965. 14. A biogeographic account of the herpetofauna of Michoacan, Mexico. By William E. Duellman. Pp. 627-709, pls. 29-36, 5 figures in text. December 30, 1965.