SPECIES OF THE GENUS XANTUSIA. 525 



The ground color in different specimens varies from 

 smoke gray, through many shades of yellow and brown, 

 to clove brown. Scattered granules are dark brown or 

 black. At times these dark granules are so numerous as 

 to become confluent, with a tendency to form longitu- 

 dinal lines. In other individuals they are scarcely visible. 

 Some specimens have heavy dotting on a very pale ground; 

 in others the dotting is heavy on a dark ground; many 

 show faint dots on a light ground; and several have few 

 dots on a dark ground. A yellowish line usually runs 

 back on the neck from the outer edge of each occipital 

 plate. Two similar lines are sometimes present on the 

 nape. The lower parts are creamy white, sometimes 

 clouded with brown towards the sides. The young aver- 

 age much darker than the adults.* 



mm. mm. mm. mm. mm. 



Suout to veut 47 44 42 37 22 



Tail 40t 47 61 41 24 



Hind limb 17 16 15^ 15 9^ 



Fore limb 12 11 11 lOf 7 



Shielded part of head 9| 9 9 9 6 



Suout to ear 9 ' 8| 8 8 5| 



Snout to anterior gular fold 9 8^ 8 8 5^ 



Snout to posterior gular fold 15 15 14 13 9 



Base of fifth to end of foiirth toe 6J 6 5| 5| 4 



History. — The first representatives of Xmitusia vigilis 

 were found at Fort Tejon, California, by Mr. John Xan- 

 tus, who furnished the three specimens upon which Pro- 

 fessor Baird based his original description, published in 

 the Proceedings of the Academy of Natural Sciences of 

 Philadelphia for 1858. Nothing more concerning it ap- 

 peared until May, 1893, when Dr. Stejneger recorded 

 two specimens secured by the Death Valley Expedition 

 in 1891. Nothing has been known about its habits, and 



* See remarks under Habits, p. 527. 

 t Kegrown. 



