BARBOUR AND NOBLE: THE GENUS CYCLURA. 155 



broadly in contact in the middle line of the snout; immediately 

 following the supranasals and separated by a double row of scales, 

 two large smooth prefrontals on each side, the posterior pair the 

 larger; these scales between the prefrontals as large as the scales 

 covering the frontal region; top of head behind the prefrontal region 

 covered by small, irregular polygonal shields, those on the supraocular 

 region much smaller than the others; three poorly indicated rosettes 

 of larger scales, one on the frontoparietal region and one on each side 

 of the occipital, each rosette consisting of a somewhat rounded scale 

 surrounded by a circle of subrectangular scales ; all shields on the top 

 of head smooth or very slightly swollen, occipital somewhat larger 

 than the adjacent scutes ; superciliary shields slightly larger than the 

 supraorbitals; the first two and the last two scales of this series some- 

 what elongate, canthal scale preceded by a somewhat squarish pre- 

 canthal of about the same size, a small subcanthal in contact with 

 the canthal scale anteriorly; 2 loreal scales between precanthal and 

 postnasal, squarish, not much smaller than precanthal; the rest of 

 the loreal scales small and elongate, a series of strongly keeled subocu- 

 lars not reaching the tympanum ; temporal shields small ; on the ante- 

 rior edge of the tympanum just above the angle of the mouth a group 

 of three or four large tubercular scales; below the angle of the mouth 

 five regular rows of enlarged round scales, the series running obliquely 

 forward ; supralabials low, six to below the center of the eye. Lower 

 labials larger than the supralabials, six to the center of the eye; two 

 rows of large molar scales separated posteriorly from the infralabials 

 by a single row of smaller scales; on each side of the jaws below the 

 angle of the mouth five or six regular rows of rounded scales; dorsal 

 crest interrupted on both shoulders and rump; nuchal section of the 

 crest consisting of twenty spines all of about the same width, varying 

 in height from one millimeter at the ends of the series to ten milli- 

 meters in the center; back section formed of seventy-six spines scarcely 

 over a millimeter in height, the last fourteen spines, however, over five 

 millimeters in height; caudal section formed of heavy spines about 

 four millimeters in height; scales on the upper side of the arms larger 

 than the dorsal scales, those on the fore arm a trifle larger than those 

 on the upper arm; a single series of twenty-three femoral pores; 

 inner side of second toe with one "comb," of third toe with two 

 "combs" each consisting of three lobes; tail covered with faintly 

 indicated verticils. 



Coloration: — Ground color bluish gray, heavily blotched with 

 confluent tawny yellow markings; upper and lateral surfaces of head 

 very pale yellow; tail and hind limbs darker than the rest of the body. 



