306 3. IGUANID.^ 



Sceloporus occidentalis bi-seriatus Camp, Univ. Cal. Pubis. Zoo!., Vol. 17, 

 No. 7, 1916, p. 65; Grin-vell & C.A.MP, Univ. Cal. Pubis. Z, oL, 

 Vol. 17, No. iG, 1917, p. 160; Stejneger & Barbour, Check List 

 N. Anier. Amph. Rept., 1917, p. 55; Cowles, Journ. EntomoL & 

 Zool., Pomona College, Vol. XII, No. 3, 1920, p. 66; Stephen's, 

 Trans. San Diego Soc. Nat. Hist., Vol. Ill, No. 4, 1921, p. 62; 

 Van Den-burgh & Slevin, Proc. Cal. Acad. Sci., Ser. 4, Vol. XI, 

 1921, pp. 28, 34, 40, 43, 51, 59; Nelson, Mem. Nat. Acad. Sci., 

 Vol. XVI, 1921, pp. 114, 130. 



Description. — Head and body little depressed. Nostril 

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

 iiead-shields smooth, moderately large, and very slightly 

 convex} interparietal much the largest. Frontal usu-.liv 

 divided transversely. Parietal, fronto-parietal and frontal 

 plates separated from enlarged supraoculars by a series of 

 smooth plates or granules. Superciliaries long, wide and 

 strongly imbricate. Middle subocular very long, nan-ow 

 and strongly keeled. Rostral plate of moderate height, but 

 great width. Labials long and low. Below lower labia'.s 

 and behind large pentangular symphyseal some series of 

 plates larger than gulars. Latter of moderate size, smooth, 

 imbricate, and usually emarginate posteriorly. Ear-opening 

 large, slightly oblique, with an anterior denticulation of 

 smooth acuminate scales. Back with equal-sized, keeled, 

 pointed scales, arranged in nearly parallel longitudinal rows. 

 Scales on sides similar to those on back but much smaller and 

 directed obliquely upward. No longitudinal folds, and no 

 transverse fold on throat. Superior surfaces of limbs pro- 

 vided with large keeled scales. Posterior surface of thigh 

 covered with small, acuminate, keeled scales. Ventral scales 

 much smaller than dorsals, smooth, imbricate, and usually 

 bicuspid. Tail with irregular whorls of strongly keeled and 

 pointed scales, much larger and rougher above than below. 

 Femoral pores varying in number from thirteen to nineteen 



