30 SYNOPSES AND DESCRIPTIONS. 



between the two antcorbitals. One temporal in fontact with the three 

 postorbitals. Labials 7 (6—7), third and fourth in orbit. Infralabials 7, 

 fourth largest. Submentals two pairs. Scales keeled, in 15 rows, verte- 

 bral narrow, outer broad, smooth. Yentrals 126±. Anal divided. Sub- 

 caiidals 40 j^airs. 



Light to olive brown, punctulate above and below, with about fifty-four 

 light-edged black cross-bars extending over six rows of scales, alternating 

 with shorter ones on the sides, broken into spots on the neck. A large 

 blotch behind the occiput on each side. Total length 13 in. 5 1. ; tail 2 in. 

 8 1. (From descr.) Mexican Plateau, between Valley of Mexico and the 

 Eastern Range. 



Storeria occipitomaculata, 2jI. /, fg. 2. 



Tkopidonotus occipitomaculatus Siorer, 18S9, AV/j. iV/cm. Rqit., 230. 

 Storeria occipitomaculatus Baird & Girard, 1853, Cat. N. A. Scrp., 137. 



Small, not stout, elongate, subcylindrical, belly round; head distinct, 

 dej)ressed, crown slightly convex, narrow in front; tail about one fourth of 

 the total, tapering regularly t(j a slender extremity. Eyes medium, pupil 

 round. Mouth-cleft deep, slightly curved. Head-shields nine, short, broad. 

 Rostral broader than high. Nasal divided, nostril in anterior portion. Lo- 

 real absent, rarely present (a specimen from Michigan has one on each 

 side). Two anteorbitals. Postorbitals two. Temporals 1+2. Labials 6 

 (5 — 6), low, eye over the third and fourth, penultimate larger. Infralabials 

 7 (<3 — 7), fifth largest. Submentals two pairs, posterior half as large as 

 anterior. Scales keeled, notched at the end, in 15 rows, dorsal narrow, 

 outer much broader. Ventrals 117 — 128. Anal bifid. Subcaudals 43 — 50. 



Brownish or greyish olive. A narrow band of light color on the middle 

 of the back, three scales in Avidth, inclosed by a pair of narrow black lines ; 

 on the inferior row there is a similar line or vitta. Closely examined, the 

 scales arc punctulate or mottled with black. The middle of the belly is 

 yellowish white, red in life, and becomes more olive toward the flanks. 

 Behind each angle of the mouth, and on the occiput, there is a spot of 

 light color. Under the head and neck the scales are more or less i^unctu- 

 late or clouded with brown. The markings vary from very distinct to 

 obsolete. Mississippi Valley and Eastward. 



