94 ON REPTILES COLLECTED NEAR GUAYAQUIL, ECUADOR. 



TROPIDURUS OCCIPITALIS Pet. 



Tropidurus (Lcemopristis) occipitalis Peters, 1871, 



M. B. Berl. Akad., 645. 

 Aneuporus occipitalis Bocourt, 1874, Miss. Sci. Mex., 



Kept., 215, pi. xviii, fig. 1. 

 Craniopeltis occipitalis Cope, 1876, Jour. Phil. Ac., 



(2), vm, 173. 

 Tropidurus occipitalis Boulenger, 1885, Cat. Liz., 11, 



173. 

 Tropidurus Bocourtii Boulenger, 1885, Cat. Liz., n, 



173. 



On the shields of the snout the keel is very feeble or 

 absent. The supraorbitals have faint striae. Frequently, 

 especially in the young, the occipital black spot is bordered 

 by white. The dorsal crest is very prominent on old 

 males ; it is less so on the females, and is indicated by broad 

 scales with a median keel, but without the acuminate point, 

 in the young. On the larger ones there are four (4-6) 

 acute scales on the front margin of the ear. Behind the 

 arm, extending back along the flank the male in life has a 

 group or band of red spots. The females and the young 

 do not show this but they have a narrow band of lighter 

 color from the upper edge of the arm to that of the thigh. 

 The humeral fold is usually black inside. Females and 

 young have the fold in front of this of a brilliant red 

 color. On the female the dorsal blotches are much reduced 

 and less distinct. On the male the four blotches of the 

 scapular region are large and jet black. The young ones 

 have eight or nine moderately distinct transverse bands of 

 brown between the nape and the base of the tail, the series 

 becoming more faint as continued farther back. The two 

 light bands along each flank are very distinct on the young. 



