CHAPTER XX : THE FAMILY XANTUSIIDy^ 



A Small Family of Dimimiiive Lizards — Five Species ' nhabit South- 

 western North America 



Classification and Distribution. — The Family Xantusiidce 

 is a small one, comprising three genera and a total number ot 

 seven species. Lepidophyma contains a single, Central Ameri- 

 can species; Cricosaura is also composed of one species, which 

 inhabits Cuba; Xantusia contains five species — all inhabiting 

 California and Lower California. The family is most nearly 

 allied to the Old World Lacertida:. 



The North American species are diminutive, with rather 

 cylindrical body and very short limbs. On the back and sides 

 the scales are fine and granular; the abdomen is covered with 

 plates; on the tail the scalation is in fine rings. 



The top of the head is covered with large, symmetrical shields. 

 There are three folds of skin on the throat. The species 

 have no eye-lids and with most of them the eye is very large; 

 all have a vertical (cat-like) pupil. The habit of frequently 

 changing colour has been noted among these lizards; this is 

 mainly influenced by light and temperature. 



The species of Xantusia inhabit barren or desert regions. 

 They are nocturnal in habits. 



Key to the Species 



I. Limbs very short. 



a. Length about 3 J- inches. 



Eyes large. Pale brown, speckled with dark brown. 



XANTUS'S LIZARD, X. vigiUs. 



Distribution. — Southeastern California. 

 Eye small. Dark clay color, with black specks. 

 A yellowish band on each side of back. 



gilbert's lizard, X. gilberti. 

 Distribution. — One specimen known; from Lower 

 California. 



b. Length about 5 inches. 



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