27. HETERODON 657 
with black, and may number about forty on the body and 
ten on the tail. These blotches may be nearly obsolete. On 
the sides are from two to four series of alternating dark 
spots, more or less distinct. The lower surface is yellowish 
white with black blotches on the gastrosteges, which usually 
are entirely black centrally, as are the urosteges. The head 
is light brown above with a narrow light streak across the 
frontal and supraocular plates. A second similar but less 
distinct streak just behind the rostral extends down in front 
of the eye. There are three dark blotches on the nape and 
an oblique one behind the eye. 
A living snake of this species, from Arizona, was colored 
as follows: The color above is a dull brownish yellow. The 
dark markings on the head and the lower series of lateral 
spots are olive brown. The dorsal blotches and the upper 
lateral series are dark brown with black spots on the bases 
of some of the scales. The chin, gular region, the tips of 
the gastrosteges and the edges of the lateral scales are 
white. The centers of the scales of the lowest lateral row 
are pinkish brown. The upper labials are pale straw yel- 
low. The lower surfaces of body and tail are marbled with 
deep lemon yellow and black. The iris is reddish brown. 
The tongue is black. 
Length to anus_..___ =165 267 455 470 533 532 
Length of; tail == 532 38 100 63 76 100 
Distribution—This snake occurs from southwestern 
Iowa, Kansas and Nebraska, west to Montana and south to 
Texas, New Mexico, Arizona and northern Mexico. Baird 
and Girard (1853) recorded one as having been collected 
in California by Dr. William Gambel. This specimen 
probably was mislabeled. In Arizona this species has been 
collected at Fort Whipple, at White River Canyon, at Min- 
eral Springs, Sulphur Spring Valley, Wilcox, and in “South- 
ern Arizona.” We recently secured a specimen from the 
