Hybridization Between Two Species of Garter Snakes BY HOBART M. SMITH University of Kansas Publications Museum of Natural History Volume 1, No. 4, pp. 97-100 August 15, 1946 UNIVERSITY OF KANSAS LAWRENCE 1946 UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY Editors: E. Raymond Hall, Chairman, Donald S. Farner, Donald F. Hoffmeister Volume 1, No. 4, pp. 97-100 Published August 15, 1946 UNIVERSITY OF KANSAS Lawrence, Kansas PRINTED BY FERD VOILAND, JR., STATE PRINTER TOPEKA, KANSAS 1946 21-2763 Hybridization Between Two Species of Garter Snakes By HOBART M. SMITH The chief characters distinguishing _Thamnophis radix_ (Baird and Girard) and _T. marciana_ (Baird and Girard) in southern Kansas are: _marciana_ _radix_ 1. lateral light line involving only 1. lateral light line involving the 3d scale row anteriorly. rows 3 and 4 anteriorly. 2. dorsal light line without distinct 2. dorsal light line with edges, varying in width from less straight, even edges, 1-1/2 than 1 to nearly 3 scale rows, at scale rows wide. various places on body. 3. several anterior lateral spots 3. _usually_ no anterior fused across lateral light lateral spots fused across stripes. lateral light stripes. 4. 2 posterior upper labials not 4. 2 posterior labials light-centered, unlike others. light-centered, like others. 5. A well-developed, white, 5. typically no well-developed black-edged crescent behind angle postrictal crescent. of jaws (postrictal crescent). Typical specimens of _radix_ are available from several localities in Morton County of southwestern Kansas (Spring Creek; twelve miles and eighteen miles north of Elkhart; Elkhart); from the State Lake and Meade in Meade County; from Hunters, Harper County; Coolidge, Hamilton County; and Ingalls, Gray County. Typical _marciana_ is available from Spring Creek, Morton County; Liberal, Seward County; and Clark County (no locality). An overlap of range with _radix_ is evident, and from Spring Creek in Morton County typical specimens of both species are available. Accordingly, at present, I conclude that the two forms are correctly regarded as distinct species.