160 



University of California Publications in Zoology [Vol.12 



MEASUREMENTS IN MILLIMETERS OF TWENTY-TWO FEMALES OF 



MOLOTHBVS ATEB OBSCVBUS FROM THE LOWER 



COLORADO VALLEY 



5.6% 



5.5% 



Xanthocephalus xanthocephalus (Bonaparte) 

 Yellow-headed Blackbird 



The single specimen secured, an adult male (no. 12915), was shot 

 from a flock of cowbirds at Ehrenberg, Arizona, March 28. No others 

 of the species were seen at that point. But on April 24, on the Arizona 

 side five miles north of Laguna, a male and two females were seen over- 

 head flying south. And on May 5, on the California side four miles 

 south of Potholes, a small flock of yellow-headed blackbirds was seen 

 flying north along the river bank. 



