5. SAUROMALUS 89 



meeting its fellow on the median line just behind the inser- 

 tion of the fore limbs. The belly is black, dotted and 

 spotted with red. The lower surfaces of the limbs are 

 black, spotted with yellowish white, and sparsely speckled 

 with red. The tail is either all white or white crossed by 

 wide bands of black. 



There is much variation in the coloration of this lizard, 

 especially as regards the black bands of the tail. These 

 may be present or absent in the same individual at different 

 times, and the change seems to be, at least to some extent, 

 directly under control of the animal. When the specimen 

 whose colors are described above was put in a jar with 

 chloroform, the black bands of the tail disappeared and re- 

 appeared several times before the lizard's death. Dr. 

 Stejneger has observed the same color changes and thought 

 them dependent upon the intensity of the light to which 

 the animal is exposed. 



Regarding the coloration of fresh specimens, Mr. Camp 

 notes: "Some of the specimens show a great amount of 

 red on both dorsal and ventral surfaces and a few do notj 

 some are banded on the tail and some exhibit scarcely a 

 trace of this characteristic. In a young specimen there are 

 around the tail four broad, encircling bands of brown alter- 

 nating with three circles of yellow. An adult male is 

 colored as follows: top of head dark brown, nearly black, 

 with many yellow scales scattered over the occiput and 

 head and small patches of orange in the ear just behind 

 the tympanum 5 back speckled with black scales in lichen- 

 like pattern 5 about an equal number of orange and of yel- 

 low scales, evenly dispersed, covering most of back; 

 shoulder patches large, dark brown, and dorsal surfaces of 

 limbs dark brown 5 feet spotted with yellow; head and 

 limbs beneath, black ; belly almost uniform dark morocco 

 to brick red; tail abruptly lighter than rest of body, deep 



