246 



BULLETIN 114, UNITED STATES NATIONAL MUSEUM. 



slight to render it improbable that these are the specimens from 

 which the original description of mexicana was prepared, and their 

 numbers have therefore been given above as the cotypes of this 

 form. 



Description. — Since the original description is somewhat incomplete, 

 the following is offered in its stead : Ventrals, 193 and 199 ; caudals, 55, 

 in two rows (both specimens females); supralabials, 7; infralabials 

 10, fifth largest, 5 under the last 3 upper labials; preocular single 

 except that it is divided in number 4652 on the left side; postoculars, 

 2; temporals, 2 in the first row, 3 in the second, and 4 or 5 in the 



Fig. 77.— Lampkopeltis mexicana (M.C.Z., scale pattern from no, 4653, color pattern from no. 

 652, San Luis Potosi, Mexico). About 1| x nat. size. Showing color pattern. 



third; posterior chin shields shorter than the anterior, and separated 

 from each other by 2 small scales; loreal about twice as long as high; 

 anal plate entire; scales smooth, with 2 apical pits; dorsal scale 

 rows, 23-21-19. 



Body moderately slender, tapering slightly toward the tail; belly 

 flat, meeting the sides in a rather distinct angle; head flat, distinct 

 from the neck, swollen at the temples, tapering anteriorly, snout 

 truncate; tail, 0.16 to 0.17 of the total length; eye large, its diameter 

 nearly twice the height of the third upper labials. One of the speci- 

 mens measures 803 millimeters, the other 452. 



The pattern of the body (fig. 77) recalls that of triangulum. There 

 are about 39 transversely oblong red blotches on head and tail 



