EEVISION OF THE KING SNAKES. 181 



neck (fig. 52). Anterior to the black band the head is reddish or 

 brownish to the snout, or the latter may be grayish. The markings 

 on the top of the head vary much with locality; in southern Missouri 

 and Arkansas there is much black, lightened by streaks or vague 

 spots of the ground color; in eastern Kansas the black may be 

 restricted to the tips of the parietals while the rest of the head is 

 without markings, or the black of gentilis may be more prominent; 

 eastward the markings typical of triangidum appear in varying com- 

 binations and perfection. Light, black-bordered superciliary spots 

 are generally present (fig. 52) and often there is a black line from the 

 eye to the angle of the mouth. 



Syspila is bounded on three sides by closely allied forms, from which 

 it is not separated by well-defined physical barriers. Consequently 

 difficulties in identification must be expected. From gentilis it is 

 best distinguished by the restriction of black on the head to the 

 posterior portions of the parietal plates, and the narrower black cross 

 bands on the body which do not tend to overspread the red areas 



Fig. 52.— Lampropeltis Triangulum syspila (U.S.N.M. no. 61680, Jefferson County, Missouri). 

 About IJ x nat. size. Showing typical color pattern of anterior end of body. 



dorsally; from amaura it may best be known by the greater number 

 of transverse whitish bands, usually 25 or more, the presence of 

 ventro-lateral alternating spots, and the breaking up or practical 

 absence of black on the frontal and anterior portion of the parietal 

 plates; from triangulum it may be distinguished by the smaller 

 number of dorsal saddles — 35 or less — the presence of only one series 

 of spots in alternation with the dorsal saddles, the yellow half collar 

 behind the head, the incompleteness of the head pattern of triangulum, 

 and the generally red color of the dorsal saddles as contrasted with 

 the usually brown or gray in triangulum (See also under Variation in 

 triangulum, p. 200). 



The dentition, as indicated by a few specimens, is as follows: 

 Maxillaries, 11 to 13, the last 2 a little larger; mandibulars 11 to 14, 

 the anterior the largest; palatines, 10, 11, or 12; pterygoids, 17 to 20. 



Range. — As here defined, syspila is found from the ninety-seventh 

 meridian north to northwestern Iowa, south to southeastern Okla- 

 homa, and east to western and southern Illinois, southern Indiana, 

 and extreme southwestern Ohio. It also may be expected in western 



