4 University of Michigan 



V. White bars on prefrontals occupying less than half the area of these 

 scutes; frontal plate uniform black, or with the white restricted to a 

 narrow transverse bar at its anterior end; no white on parietals; in- 



fralabials usually 9 L. gctulus yumcnsis Blanchard. 



(Southern Arizona, extreme southeastern California, northeastern Lower 

 Cahfomia, and northwestern Sonora.) 



P. White bars on prefrontals occupying more than half the area of these 

 plates; frontal plate with prominent white markings, or at least with a 

 central spot of white; each parietal with one or more white spots; in- 



frabials usually 10 L. geluhis conjimcta (Cope). 



(Southern Lower California.) 



b'. Pattern with red, or with dorsal blotches of brown, gray, or red, with black 

 borders. 



m'. Pattern of black-edged dorsal blotches of brownish or dark red, 

 only narrowly- in contact with the fifth row of scales or extending no 

 lower than the sixth or seventh rows. . . . Calligaster group. 



n'. Blotches less than 40 L. leoiiis (Gunther). 



(Nuevo Leon, Mexico.) 

 n'. Blotches 45 to 80. 



o'. Scale rows 25 to 27 on middle of body; dorsal blotches with 

 concave anterior and posterior margins; infralabials 9 or 10, 



rarely 8 L. calligaster (Harlan). 



(Western Texas to Mississippi, north to Indiana and north- 

 west to Minnesota, thence south to Texas.) 

 o'. Scale rows 23 or 21 on middle of bodj'; dorsal blotches with 

 straight or convex anterior and posterior margins; infra- 

 labials 8, less often g. . . L. rhombomaculata (Holbrook). 

 (Mobile, Alabama, to Knoxville, Tennessee, north to Mary- 

 land, and south to central Florida.) 

 m^ Pattern in rings; or, if in blotches or saddles of brown, gray, or red, 

 these broadly in contact with the fifth or a lower row of scales. 



p'. WTiitish cross-bands on body and tail less than 40; or, if 

 more than 40, the snout not uniformlj' whitish. 



q'. Whitish cross-bands little if any widened on the lower 

 rows of dorsal scales, and the scale rows more than 1 7 

 on the anterior portion of the body. 

 r'. Red scales usually tipped with black. 



s". Snout black, with usually a Ught transverse 

 bar on or near the prefrontals; two temporals 

 in the first row; caudals usually not less than 



49. L. polyzona Cope. 



(Southern Mexico to Costa Rica.) 



