8. CALLISAURUS 149 



upper surface of snout. Supraocular regions covered with 

 small plates and separated from each other by one or two 

 rows of slightly larger plates. Upper head plates (except 

 interparietal) small and irregular, largest on frontal and 

 prefrontal regions, everywhere smooth and rather flat. Sev- 

 eral subocular plates, middle one very long and strongly 

 keeled. Superciliaries rather small, but strongly imbricate. 

 Eye-lids bearing a well-developed fringe. Supralabials 

 strongly imbricate, and produced laterally so as to form a 

 series of curves when seen from above. Infralabials small, 

 juxtaposed. Below them, several series of flat sublabial plates. 

 Gulars granular and smooth, growing larger and imbricate 

 on posterior fold. Back and sides covered with small flat- 

 tened granules, which change gradually into much larger 

 smooth ventrals. A dermal fold usually extending along 

 each side between limbs. Tail of moderate length, much 

 flattened, its scales slightly imbricate, and along its edge, 

 pointed. Limbs very long and slender. Ear-opening large, 

 without denticulation. Femoral pores varying from 1 1 to 

 17 j average in 87 thighs, 13.10. 



The general color above is grayish, dotted or spotted 

 with white or pale gray, often more or less suffused with 

 brown, pink or red, and often with indications of dark dorsal 

 blotches which are most distinct in females and young. The 

 top of the head is gray, brown, cream, or olive, sometimes 

 clouded with dark slaty gray. The upper surfaces of the 

 limbs are crossed by more or less obsolete bands of dark 

 brown or blackish slate. A dark stripe, bordered above and 

 below with white, runs along the back of the thigh. The 

 upper surface of the tail is gray or light brown, with cross- 

 bars of very dark blackish brown or black in females and 

 black in males. The posterior borders of these bars are 

 nearly straight or but little undulate at least from the 

 middle to the end of the tail. The throat is white, more 



