Dr. Doris M. Cochran of the United States National Museum kindly furnished information concerning the type specimen of Eutainia dorsalis formerly in the National Museum collection but now lost. Dr. James S. Findley of the University of New Mexico and Dr. Ralph J. Raitt of New Mexico State University contributed habitat notes and records of specimens and loaned us critical specimens of T. sirtalis from New Mexico. Drs. George F. Baxter of the University of Wyoming, John M. Legler of the University of Utah, and Wilmer W. Tanner of Brigham Young University kindly provided us with information concerning the specimens in the collections of their respective institutions, and their personal observations concerning the distribution of garter snakes in their states. Alice V. Fitch, Chester W. Fitch and Donald S. Fitch assisted in the collection of fresh specimens in Oregon and Utah and the unsuccessful search of many a mosquito-infested meadow in southern Wyoming and northwestern Colorado in July, 1959. Dr. R. G. Webb made available his MS on reptiles of Oklahoma.

This taxonomic study of garter snakes originated as a by-product of the senior author's study of ecology and economic bearing of snakes in the central Plains Region of the United States, for which support received from the National Science Foundation is gratefully acknowledged.