SYNOPSES AND DESCRIPTIONS. 13 
pairs, second half as large as first. Scales in 15-17 rows, some of the 
dorsals with keels. Anal entire. Subcaudals in two rows. 
Dark brown or black. The light color of the throat and chin-shields 
extends upward as an occipital collar, Flanks with widely separated, 
wedge-shaped, vertical bars of light color, which frequently meet in their 
points on the back, forming transverse bands to the sides of the belly. 
Belly much spotted with dark posteriorly. 
Hab. Mexico and Central America. 
LEPTOGNATHUS DUMERILII. 
Jan, 1870, Icon. Livr. XXXVI, pl. V, fig. 2. 
Scales smooth, in 17 rows. The principal difference between this species 
and the preceding is in the carination of the scales. It is altogether likely 
that individual variations in this respect will do away with its value, in 
which case the form cannot even stand as a variety. 
LEPTOGNATHUS NEBULATUS. 
PETALOGNATHUS NEBULATUS Duméril, 1852 (1853), Mem. de V Acad. Sci. XXITT, 466. 
Slender, elongate, much compressed; head large, distinct, crown slightly 
convex, muzzle high; tail slender, tapering. Eye large, pupil erect. Head- 
shields short, broad. Rostral as broad as high. Nasal in two parts, nos- 
tril principally in anterior. Loreal and preocular fused. One preocular, 
sometimes a small plate at its lower posterior angle. Postoculars two. 
Temporals 1+2+3. Labials seven, fourth and fifth below the eye,.sixth 
largest. Infralabials nine, sixth largest. Submentals three pairs (2—3), 
anterior larger. Scales smooth, in 15 rows, several of the dorsal broader, 
the median broader than long. Ventrals 185—197. Anal entire. Sub- 
caudals 87—90 pairs. 
Greyish-brown, mottled with brown, with more or less irregular narrow 
transverse white-edged bands of brown. A series of large blotches on each 
side of the abdomen, apparently separated at the median line, more or less 
confluent with the dorsal bands, and frequently with them forming com- 
plete rings aroumd the body. Belly yellowish, clouded and spotted with 
brown. Head brown, irregularly marked with white (yellow). First 
brown band immediately behind the head.- Tail darker. Total length 
17 inches; tail 4. Total length 144 in.; tail 33. Hab, Mexico to Brazil; 
West Indies, 
