776 REPORT OF NATIONAL MUSEUM, 1898. 



oue-lialf long, and separated by interspaces of one and one-half scales, 

 which are ijretty constant throughout, though rather narrower on the 

 tail. On each side of the dorsal row may be made out, under favora- 

 ble circumstances, four alternating rows of blotches; the first on the 

 contiguous edges of the scales of the first and second exterior dorsal 

 rows; the second on the scales of the third row, and the adjacent edges 

 of those in the second and fourth; the third on the scales of the fourth, 

 fifth, and sixth, and the adjacent edges of the third and seventh, and 

 the fourth on the scales of the sixth, seventh, and eighth rows, and 

 the adjacent edges of those of the fifth. This last is opposite the 

 intervals of the dorsal series; the rest alternate with it. The central 

 inferior surface of the abdominal scutellte is black, sharply variegated 

 with quadrate spots of yellowish white; the portion of the scutellae 

 entering into the side of the body is yellowish white, with that part 

 opposite the dorsal intervals dark brown, thus, in fact, constituting a 

 fifth lateral series of blotches, alternating with the lowest already men- 

 tioned. The throat and chin are unspotted. The head is light brown, 

 with a narrow whitish line finely margined before and behind with 

 black, which crosses in front of the center of the vertical and through 

 the middle of the superciliaries; a second similar but more indistinct 

 line runs parallel to this, just behind the rostral, and extending down 

 in front of the eye. A third equally indistinct and similar line crosses 

 the posterior angle of the vertical and runs back on the side of the 

 neck, behind the labials and temporal shields. There is a broad brown 

 patch from the back part of the eye to the angle of the mouth, across 

 the penultimate and last labial. The coloration is thus very different 

 from that of H. n. simus, where there is a distinct narrow black band 

 across the forehead scarcely involving the vertical, and passing through 

 the eye to the angle of the mouth across the last labial. Behind this 

 a much broader yellowish band, continued without interruption into 

 the neck behind the angle of the mouth. In H. n. nasicus the most con- 

 spicuous feature is a narrow white band, much narrower than the 

 darker iiatch before and behind it. The dark patch, to the angle of 

 the mouth, is much broader, continuous, as it were, with the broad bar 

 between the middle and anterior light lines, which corresponds with 

 the narrow black line of H. n. shnus. The other distinguishing features 

 are evident. The three dark patches behind the head are much as in 

 H. n. simus. 



In the larger specimens from Sonora and the copper mines the 

 ground color is yellowish gray, each scale minutely punctate with 

 brown. The blotches are all obsolete, only one dorsal and two lateral 

 on each side being defined by darker shades. The blotches on the 

 sides of the abdomen are wanting, but the black in the middle is 

 strongly marked. The other chaiacters, however, are ])reserved, except 

 that the exterior row of dorsal scales is more or less carinated. 



