342 3. IGUANID& 



68. Sceloporus monserratensis Van Denburgh 

 and Slevin 



MONSERRATE ISLAND SCALY LlZARD 



Sceloporus monserratensis VAN DENBURGH & SLEVIN, Proc. Cal. Acad. 

 Sci., Ser. 4, Vol. XI, No. 17, 1921, p. 396 (type locality, Monserrate 

 Island, Gulf of California, Mexico). 



Description. Head and body little depressed. Nasal 

 opening slightly nearer to end of snout than to orbit. Upper 

 head-plates smooth, often a little convex, and sometimes 

 slightly imbricate - y interparietal largest. Frontal divided 

 transversely. Parietal and frontoparietal plates not separ- 

 ated from large supraoculars. Latter very broad. Super- 

 ciliaries strongly imbricate. Middle subocular very long, 

 narrow, and strongly keeled. Rostral plate wider than high. 

 Labials long but very low, inferior a little larger than super- 

 ior. Symphyseal large, followed by several plates larger 

 than gulars and separated from lower labials by one to 

 three rows of narrow sublabials. Gular region with scales 

 smooth, bicuspid, and strongly imbricate, as are also scales 

 on belly. Ear-opening large, nearly vertical, and protected 

 by a series of very long, acuminate scales. Dorsal scales 

 large, equal in size or larger centrally, rather weakly or 

 strongly keeled, but strongly mucronate, arranged in nearly 

 parallel longitudinal rows. Scales of sides pointed obliquely 

 upward, and changing gradually from carinate dorsals to 

 smaller smooth ventrals. No longitudinal dermal folds. 

 Upper surfaces of limbs provided with strongly keeled and 

 pointed scales. Scales on posterior surface of thigh large, 

 acuminate, strongly keeled and pointed. Upper caudal 

 scales similar to dorsals, but often having longer points. 

 Femoral pores varying in number from 18 to 22 on each 

 thigh 5 average in 48 thighs, 19.7. Five or six dorsal scales 

 in adults equaling length of shielded part of head. Num- 



