84 Aphelocoma ultramarina Nov. 6-10 Casita, 40 km. S Nogales, 3300 feet, Sonora. Feeding flocks settled on a hillside in areas where some ground cover was available and then forage either over the ground or in the peripheral foliage of oaks. In feeding activities [illegible] sideways hopping on the ground, and craning and bending about foliage masses, this species suggested A. coerulescens. It was observed to pound bits of food, probably acorns, as does the scrub jay. I was impressed with the silence of the feeding flock; often only after shooting at some other species would I realize that a flock had been nearly all the time but practically silent. Also, it was realized that some of these silent flocks were merely quietly resting in one or two oaks. The flight is direct and strong; the impression one gets being that of a bird distinctly heavier than our coastal scrub jay. Individually or in flocks, these jays would undertake long flights down or up slopes, across canyons at considerable heights above the woodland in a manner rare to A. coerulescens. In flocking behavior, movement, and even in call-notes (manner of calling and to some extent quality of notes), these jays suggested Cyanoccephalus.