BARBOUR AND NOBLE: THE GENUS CYCLURA. 159 
series separated by a double row of rather large irregular scales. 
Frontal and frontoparietal regions with small and irregular scales 
very slightly keeled, each scale depressed so as to make the interstices 
stand out like a network. Supraorbital semicircles differentiated 
only posteriorly where they are formed of broad, slightly keeled scales. 
Occipital region with a huge swelling on each side, each covered with 
flat scales. Canthus rostralis formed of a group of three, medium 
sized keeled scales. Dorsal crest not interrupted on either shoulder 
or rump; largest spine about a centimeter in length; fifty spines in 
the crest from shoulders to rump. Color above mud-gray washed 
with green anteriorly; a series of straw color stipplings covering the 
dorsal and lateral surfaces, these stipplings uniting into blotches 
posteriorly. 
Habitat: — Jamaica, where it is now exceedingly rare, being only 
found on a few islets off the coast where the mongoose has not been 
introduced. The mongoose eats the eggs and the very young. 
Description: — Adult male, M. C. Z. 9397 Goat Island, near Old 
Harbour, Jamaica, 1914, Arthur Perrin. 
Rostral wider than mental, separated from the nasals by several 
rows of very fine granules; nasal large, ovoid and perforated on the 
posterior half by a large semicircular nostril; immediately behind and 
adjoining the nasal, a series of three large shields, slightly swollen 
and a trifle convex; the series separated by a double row of rather 
large irregular scales; the last pair of scales in the series about twice 
as large as the anterior pair; the scales of each series broadly in contact 
with each other without any intervening scales; a pair of large tri- 
angular postnasals; scales of the frontoparietal region all small and 
irregular, each scale depressed so that the interstices stand out like 
network; supraorbital semicircles only evident posteriorly, formed of 
broad, slightly keeled scales; scales covering the supraocular region 
smaller than those of the frontal region, each scale very slightly 
keeled; occipital smaller than nasals, located well forward between 
the semicircles from which it is separated by three rows of scales; 
occipital region swollen out into a pair of huge humps, each covered 
with a group of rather large, flat, slightly keeled scales; two rows of 
strongly keeled supraciliaries; canthus rostralis consisting of a group 
of three, medium sized keeled scales; a well-developed series of 
strongly keeled suboculars continued backward as a supratympanic 
series to above the middle of the ear; six supralabials to the middle 
of the eye; a series of very small scales separating the suboculars and 
the supralabials; above the angle of the mouth and in front of the 
