182 3. IGUANID.^ 



cc. — Throat mottled or with transverse markings, 

 without definite rounded spots. 



U. slevini. — p. 19+. 



— Largest dorsals squamosa, usually imbricate, larger 

 than the granular laterals; adults less than 15 mm. 

 from snout to anus; often a blackish blotch in front 

 of shoulder or a blue blotch behind axilla. 

 bb. — A longitudinal dorsolateral line or dermal fold, 

 usually with some enlarged scales on it; usually a 

 second, lateral fold; no small, rounded blue blotch 

 behind axilla . (Subgenus Urosaurus). 

 ccc. — Dorsal scales of one to three (usually two) 

 median longitudinal rows much smaller than 

 those of one to three rows just external to them, 

 d. — Dorsolateral fold or line with very large, 

 closely set enlarged scales or tubercles; tail 

 twice length of head and body. 

 About two rows of single, strongly keeled, 

 enlarged dorsal scales on each side of the 

 smaller mid-dorsal series. Clarion Island. 

 U. clarionensis. — p. 196. 

 d*. — Dorsolateral fold or line without enlarged 

 scales or tubercles, or with enlarged scales or 

 tubercles at considerable intervals. 

 e. — Thighs without keeled scales; larger, adults 

 usually exceeding sixty millimeters from 

 snout to anus. Socorro Island. 



U. auriculata. — p. 197. 

 e'. — Thighs with keeled scales; smaller, adults 

 usually less than sixty millimeters from 

 snout to anus, 

 f. — Series of enlarged dorsal scales usually be- 

 ginning in front of a line connecting inser- 

 tions of fore-limbs; dorsolateral tubercles 



