160 BULLETIN 114, UNITED STATES NATIONAL MUSEUM. 



the form from northeastern Mexico (that the black on the belly is 

 not solid between the yellow rings is because it is the anterior end 

 of the body that is sho^vn; this is the usual condition with typical 

 specimens). If we are correct in judging Jan's conjuncta to be the 

 equivalent of Kennicott's annulata, then the occipitalis of Cope is 

 also a synonym of annulata, for he expressly states (1891, 609) that 

 his name is a synonym of conjuncta Jan, having, in 1888, v/hen he 

 proposed the name occipitalis, apparently overlooked the name 

 conjuncta. 



Description. — The scutellation based upon twelve specimens is 

 as follows: Ventral plates, 197 to 212; caudals, 40 to 57; supralabials, 

 7, rarely 8; infralabials, 9, sometimes 10; a single preocular, 2 postocu- 

 lars; temporals generally 2 + 3 + 4; posterior chin shields usually in 

 contact with each other, sometimes separated by a small scale, 

 shorter than, or about as long as, the anterior; loreal longer than 

 high; scale rows usually 21-19 or 21-23-21-19. 



The bodily proportions are much the same as for the rest of the 

 group. The head, however, is less distinct from the neck, and the 

 tail, in the vicinity of the type locality, is rather long. For this 

 region the proportion of the tail to the total length ranges from 0.138 

 to 0.167 for eight females, averaging 0.151; two males have the pro- 

 portions 0.150 and 0.156; and for a female from Puebla, Mexico, it 

 is 0.123. The largest specimens examined v/ere from Montemoreles 

 and Peubla, Mexico; each measured 836 mm. 



The pattern (fig. 66) is composed of from 19 to 26 white or yellow 

 rings, from head to tip of tail, bordered by black and separated by 

 broader areas of red. The white rings are about IJ to 2 scales wide, 

 uniform in diameter or a little widened on the first row of scales, 

 completed upon the belly or partially interrupted there with black, 

 and usually mottled on the sides with darker. The black rings are 

 generally widest on the middorsal line, sometimes even confluent 

 here across the red, and narrowest on the first row of scales. They 

 are continuous across the belly. The red areas, except the first ones, 

 are not completed across the belly, except partially so in individuals 

 from the northern limits of the range, but are here replaced by black. 

 The belly thus normally presents a series of large quadrate black areas 

 separated by much narrower bands of white or yellow. 



The head is normally black from the tip of the snout back to the 

 posterior portion of the parietals and the fifth to seventh upper 

 labials. In the northern portion of the range, lightening of the snout 

 begins in the loreal and nasal region and the lower side of the rostral 

 plate. The chin is more or less mottled with black and white. The 

 first black ring is usually complete on the neck. 



Dental characteristics, as exhibited by ^ve specimens, are as fol- 

 lows: Maxillary teeth, 13 to 15, subequal except the last two which 



