48. CROTALUS 909 
f.—Dorsal rhombs usually not enclosing light later- 
al areas. 
C. atrox.—p. 914. 
f°—Dorsal rhombs usually enclosing light lateral 
areas as pale as the ground color. Tortuga 
Island. 
C. tortugensis.—p. 918. 
e.—First supralabial usually divided transversely; 
general coloration reddish, pinkish or yellowish. 
ff.—General coloration reddish, pinkish or yellow- 
ish; markings duller and less definite; dorsal 
blotches not usually completely surrounded by 
light margins; gastrosteges usually more num- 
erous. 
C. exsul.— p. 919. 
ff'.—General coloration yellowish; markings much 
brighter and more definite, less punctulate; 
dorsal blotches usually completely surrounded 
by light margins; gastrosteges usually fewer. 
C. lucasensis.—p. 925. 
d’.—Tail brownish or grayish with darker brown (rare- 
ly in part blackish) cross-bands; light postocular 
line, if present, reaching row of scales next above 
supralabials at or posterior to corner of mouth, 
in at all, 
ee.—Intervals between dorsal dark blotches less than 
length of blotches along midline. 
£ff.—Dorsal blotches large, forming a single series. 
g.—Rostral not wider than high. 
h.—Gastrosteges average more numerous (158 
to 189); no vertical white line across mid- 
dle of rostral plate nor two white lines on 
side of head. 
