320 3. IGUANIDM 



eral regions. The sides are brownish or grayish, mottled 

 with darker brown and dotted or suffused with green or pale 

 blue. The head is usually crossed by narrow brown lines, 

 more or less irregular in distribution. A brown line con- 

 nects the orbit and upper corner of the ear, and is continued 

 backward on the neck. There is a large blue patch on each 

 side of the belly, bordered internally with black in highly 

 colored males. The chin and throat are blue, pale anteriorly 

 and changing to black posteriorly, crossed by narrow oblique 

 black lines which converge posteriorly and blend with the 

 black patches on the throat and in front of the shoulders in 

 males. There is a white patch at each side the anus, and a 

 yellowish white band along the series of femoral pores. 



Remarks. — In general appearance, this lizard is similar 

 to S. occideyitaUs occidentalis but differs in a number of 

 respects. The less highly colored young males from Santa 

 Rosa Island show a single median blue throat patch, as in 

 5. o. biseriatus., indicating relationship to that subspecies. 

 Specimens from San Miguel Island all have the frontopari- 

 e':p-i plates in contact with the enlarged supraoculars. This 

 arrangement is found in a minority of the specimens from 

 Santa Rosa and Santa Cruz islands. The coloration of 

 specimens from the three islands, however, seems to be 

 identical, and justifies one in regarding this lizard as a dis- 

 tinct species, since intergradation in this respect with either 

 of the mainland relatives, S. o. occidentalis and S. o. biseri- 



