118 BULLETIN 114, UK-iTED STATES NATIONAL MUSEUM. 



extends thus forward to between the eyes, where the forks may- 

 unite again. From behind each eye a long black-bordered brown 

 band about two scales wide extends backward on top of the neck. 

 From the eye to the angle of the mouth there is a narrow dark band. 

 Thus there is a strip of the ground color from the upper postocular 

 to the last supralabial. The other head and throat plates are mostly 

 light-colored. The belly may be faintly or heavily checked with 





Fig. 39.— Typical pattern of Lampropeltis calligaster (U.S.N.M. no. 1593, cotype of 0phibolu3 

 EVANSn Kennicott from Central Illinois). About 1| X nat. size 



small quadrate brownish or yellowish blotches, or nearly immaculate 

 except for the ends of the ventrals. 



This pattern is well defined in young individuals, but in many 

 adults the markings, particularly of the head, lose their distinctness 

 and become greatly obscured by a darkening of the ground color. 

 Such darkening appears to be accompanied by an alternate length- 

 wise lightening and intensification of pigment, producing a rather 

 prominently striped effect (fig. 40). Throughout the middorsal 

 line there is a light stripe; bordering this on either side is a dark 

 band which passes through the lower portions of the dorsal blotches. 

 Below this, and between the dorsal and lateral series, is a light band; 

 then below this last and passing through the upper lateral series of 

 blotches is another dark band. The two or three lowest rows of 



