BARBOUR AND NOBLE: THE GENUS CYCLURA. 153 



some scarcely keeled; a well-developed series of keeled suboculars 

 continued backward as a supratympanic series, eight supralabials to 

 the middle of the eye; a series of four or five rows of small scales 

 separating the supralabials from the suboculars ; on the anterior edge 

 of the ear a single row of large, strongly tubercular scales preceded by 

 a group of smaller, tubercular scales grading off in size anteriorly; 

 below the angle of the mouth a group of large tubercular scales, in 

 close contact with each other, grading off in size anteriorly; eight 

 infralabials to the middle of the eye; a single row of large slightly 

 swollen malar scales; a disconnected single row of small scales be- 

 tween some of the malars and infralabials ; dorsal scales slightly larger 

 than the ventrals, about twelve contained in the vertical diameter of 

 the tympanum; from the nuchal fold along the median line of the 

 neck and back a row of very low blunt spines, the largest scarcely 

 three millimeters high; the crest greatly diminished but not inter- 

 rupted, however, on the rump; 60 spines in the dorsal crest from 

 shoulder to rump; upper surface of limbs with slightly imbricated, 

 keeled posteriorly pointed scales, considerably larger than the body- 

 scales; scales covering the upper surface of the fore arm and tibia 

 much larger than those covering the upper arm and femur; on the 

 upper arm about nine on the lower about seven of these scales to the 

 vertical diameter of the tympanum; a single series of twenty-one 

 femoral pores; inner side of the second toe with one comb of third 

 with two combs, each consisting of three lobes. Tail compressed, 

 covered with obliquely keeled scales in vertical rows, forming distinct 

 verticils; tail surmounted by a serrated crest, similar to the body 

 crest, but formed of slightly longer spines anteriorly. 



Coloration. Ground tone of dorsal surface grayish brown, sprinkled 

 very slightly with yellowish gray; the dorsal crest and spinal region 

 tinged with straw color; upper surface of the head tinged with bluish; 

 muzzle and sides of head brownish black, gular region chalky white in 

 strong contrast to the rest of the ventral surface; whole ventral 

 surface somewhat lighter than dorsal surface; limiting row of the 

 verticils bluish gray. 



Material examined. 

 We have only seen a single specimen of this species, the type. 



