160 BULLETIN 191, UNITED STATES NATIONAL MUSEUM 



One o£ these attentions is the preening of one member of the pair by 

 the other, presumably the male. I had opportunity to watch this at 

 close range at the San Diego Zoo. In a cage of mixed kinds of corvids 

 there were two yellow-billed magpies, considered by their keeper to be 

 a mated pair. During most of the time I watched, one bird, apparently 

 the male, was perched close to the other, and was working its opened 

 bill through the feathers about, mostly on top of, the head of its mate. 

 This is just what I have seen mated pairs do many times in the wild. 

 The feathers were preened and worked over just as if the bird were 

 searching for parasites, but the real significance of the behavior must be 

 connected with mating. Most of the wild birds observed behaving in 

 this manner have been perched directly on the nest or on a limb very 

 close to it. 



The most conspicuous habit in the series connected with courtship in 

 the magpies is mate-feeding by the male. This begins to be developed 

 at about the time the nest is completed and becomes well established by 

 tlie time incubation begins. One demonstration of an early stage in the 

 development of this habit was watched on a day early in March. One 

 magpie was walking in a circle about 5 feet in diameter. It was flutter- 

 ing its wings and walking around another magpie, which it seemed to 

 keep in the circle. The second bird walked just a few inches ahead of 

 the fluttering one, which kept its tail turned toward the center of the 

 circle. When a third magpie lit nearby, the antics of the two birds 

 stopped and they began to feed. 



Another pair demonstrated the early stages in the establishment of the 

 mate-feeding behavior. These two birds were foraging in a grainfield 

 where the ground was nearly bare. The male walked about, paying 

 little attention to its mate. The female at first ran after and put herself 

 in front of the male, facing him with bill open, head lowered, and wings 

 quivering. This bird seemed to hold its wings less widely opened and 

 to move them more rapidly than did other individuals noted. The re- 

 sponse of the male was merely to turn and walk in another direction. 

 Once the female picked at some object on the ground, and immediately 

 the wing-quivering reaction was aroused, and the bird hurried over to 

 its mate, but again the response was negative. After about ten fruitless 

 beggings the female began to pick up objects, presumably food, and for 

 the next three or four minutes she was picking almost continuously, 

 with only an occasional tendency to flutter the wings slightly. Next, the 

 male flew to the top of a fence post. The female flew to the next post, 

 and immediately upon alighting her wings were opened slightly. When 

 the birds were on the ground, the female picked at objects much oftener 

 than did the male. The supposition was that these actions were pre- 

 Uminarv to actual incubation which was to begin shortly. 



