72 CALIFORNIA ACADEMY OF SCIENCES. 



less than twice as long as head and body. Males with 

 enlarged postanal plates. 



The general color above is grayish or yellowish brown, 

 paler and somewhat ochraceous on the head and the 

 base of the tail, darkest along the upper lateral fold, and 

 crossed by from six to eight light-edged bars of black or 

 brown. These cross-bars are often very indistinct, 

 usually interrupted on the middle of the back, and 

 sometimes alternating with those on the opposite side. 

 The light edgings of the dorsal bars may be either blue 

 or yellow. The sides are often dotted with one or both 

 of these colors. Narrow dark lines cross the top of the 

 head, the most distinct being on the supraocular and 

 frontal regions. In young specimens the dark coloring 

 of the upper lateral fold is continued forward as a line, 

 passing just above the ear-opening, crossing the orbit, 

 and ending at the nostril. The tail is indistinctly 

 ringed with dusky and often tinged with ochraceous. 

 The lower surfaces are white, more or less dotted or 

 suffused with dark brown or black. Males usually have 

 a blue patch on each side of the belly and an area of 

 lemon yellow, which sometimes acquires a tinge of blue, 

 on the center of the throat. 



Length to anus 30 36 49 54 55 59 



Length of tail 49 58 85 95 102 



Gular fold to anus 18 23 32 35 37 37 



Snout to ear 8 9 11 12 12 13 



Width of head 6 7 9 9 10 10 



Fore limb 14 16 22 23 26 27 



Hind limb 18 24 31 36 37 38 



Base of fifth to end of fourth toe 7 10 14 14 14 16 



Distribution. The Tree Uta has been found in Cali- 

 fornia only on the banks of the Colorado River near 

 Fort Yuma, San Diego County. Its range seems not to 

 extend much farther north, for a careful search failed to 



