The Family Xantusiidae 



the back, but may be again discerned over the thighs. The 

 abdomen is yellowisli white. 



Dimensions. — Total length about 3 inches; tail, li inches. 



Distribution. — One specimen known and taken at San 

 Francisquito, Sierra Laguna, Lower California. 



Henshaw's Lizard, Xantusia henshawi, Stejnegcr, differs 

 from the species already described in having fourteen (longitudi- 

 nal) series of plates on the abdomen. The eye is large. 



Colouration. — Blackish brown above, irregularly marbled 

 with cream-coloured lines; on the tail these show a tendency 

 to form cross-bands. White beneath. 



Dimensions. — Total Length 5f inches. 



Length of Tail 3I 



Distribution. — The species has been found only at Witch 

 Creek, San Diego County, California — in the chaparral belt. 



Habits. — Concerning the habits, Mr. Van Denburgh remarks: 



"Here this species lives among the numerous granite 

 boulders, and comes out into the narrower crevices between them 

 a few minutes before dark. It is, therefore, practicable to hunt 

 for it only about fifteen or twenty minutes each day. If a bit 

 of string or a straw be introduced into the domain of one of these 

 lizards it will often be seized, the reptile apparently mistaking 

 it for some stray insect." 



Rivers' Lizard, Xantusia riversiana, Cope. — The largest 

 species. Differs from the others in having two series of small 

 plates over the eye and the plates of the abdomen in sixteen 

 (longitudinal) series. 



Colouration. — Gray or brown with irregularly-scattered 

 brown or black spots. On some specimens the spots fuse into 

 lines. 



Dimensions. — Total Length 7 inches. 



Length of Tail 3^ 



Length of Front Limb i J 



" " Hind " li " 



Length of Head i| " 



Distribution. — San Clemente, San Nicholas and Santa 

 Catalina Islands, off coast of California. 



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