68 BULLETIN 17 5, UNITED STATES NATIONAL MUSEUM 



the other forms under consideration the anterior spots are always in 

 distinct contrast with the light ground color, and the total number of 

 spots always exceeds 40. 



Description.— The body is rather stout, and the snout is narrow and 

 rather pointed, protruding slightly beyond the lower jaw. The tail 

 length varies from 0.118 to 0.147 of the total length, while the aver- 

 age for the series examined is 0.133. The longest specimen examined 

 was 1,800 mm. long. 



The dorsal scale formula ranges from 29-29-19 to 31-35-23. The 

 number of scales around the neck is 29 to 31, oftenest 29 ; the maximum 

 number of rows 29 to 35, usually 31; the minimum number just 

 anterior to the vent 19 to 23. The remaining scale characters, as 

 based on the small number of specimens available, are as follows: 

 Ventrals 218 to 235 (average 224.5); caudals 53 to 67 (average 59.5); 

 supralabials generally 8, but sometimes 9, with the fourth usually, 

 the fifth occasionally, in contact with the eye; infralabials 12 to 15; 

 preoculars usually single, rarely 2 ; postoculars oftenest 3, occasionally 

 4; loreal usually present; azygos never present between frontal and 

 prefrontals, but occasionally a small azygos present on each side be- 

 tween prefrontal and preocular; rostral very long and narrow, at 

 least twice as long as broad, and penetrating at least one-half, and 

 generally more, of the distance between the internasals; frontal gen- 

 erally undivided, but occasionally split for as much as one-half of its 

 length. 



The dentition is as follows: Mandibular teeth 17 to 19, decreasing 

 slightly in size posteriorly; maxillary teeth 16 to 17, decreasing in size 

 posteriorly; palatines 9 to 10, slightly smaller than mandibular and 

 maxillary teeth; pterygoids 7 to 10, smaller than the palatines, and 

 decreasing slightly in size posteriorly. 



The dorsum is pied brown and white, or reddish and white. Except 

 in young specimens the spots are so blended with the brownish ground 

 on the anterior part of the body that they are almost or entirely ob- 

 scured and are readily distinguishable only on the posterior part and 

 on the tail. The spots when distinct number from 26 to 29 on the 

 body and range from 5 to 10 on the tail. They are each 4 to 8 scales 

 in length and 10 to 12 scales in width and are separated by interspaces 

 of 3 to 6 scales in length. These interspaces, as in melanoleucus, 

 may bear each a central narrow dark spot or bar. In color the spots 

 are a rusty brown and in some specimens even become a bright red on 

 the posterior part of the dorsum and on the tail. One or more irregu- 

 lar series of spots are present on either side, but anteriorly these are 

 so blended with the ground color as to be indistinguishable, and pos- 

 teriorly they are fused either with the lateral ventral or the median 

 dorsal spots. The belly bears a lateral series of small spots on each 

 side of the ventral scutes, which more or less intrude on the sides by 



