56 BULLETIN 174, UNITED STATES NATIONAL MUSEUM 



(rarely more) above the ground, generally in dead or dying wood, 

 sometimes in a solid branch. The entrance, one and a quarter inches 

 in diameter, is just large enough to admit the bird's body, and is per- 

 fectly circular unless some bits of soft wood chip off. The cavity is 

 roughly gourd-shaped, turning downward and widening soon after 

 penetrating the wood and extends to a depth varying normally from 

 eight to twelve inches. Generally a few chips are left in the bottom 

 of the cavity. * 



Lewis O. Shelley says (MS.) that according to his experience "the 

 female selects the nest site on her winter, or year-round, territory." 

 He speaks of a female that in the fall "partly dug out a cavity, sup- 

 posedly for her winter quarters, but the following summer I found a 

 brood of young of this same bird occupying the nest." 



Writers are almost unanimously of the opinion that both birds of 

 the pair excavate the nest, but Shelley (MS.) states: "Of a number 

 of nests observed, I have never known the male downy to assist in 

 excavating. He often comes near when the female is working, but 

 this seems to be an understood signal for her to cease work and go off 

 in his company." 



A. Dawes DuBois, in a letter to Mr. Bent, describes the behavior of 

 a pair working jointly on a nest in Ithaca, N. Y., about 15 feet up 

 in an old stub. He says: "These birds were working the lower 

 depths. The jDartners worked alternately. First the female lighted 

 on the stub and disappeared within the cavity. Immediately she 

 thrust out her head, and, with a quick shake, disposed of a billful of 

 chips. She repeated this a number of times. She was throwing out 

 the loose chips from the bottom of the cavity. Soon she began to 

 chisel, remaining inside where we could not see her. After she had 

 been working for five or six minutes, her mate flew to the stub and 

 uttered a chirp, whereupon the female came out and flew away. 



"The male went in to continue the work by a somewhat different 

 method. He was never entirely lost to view — his tail was always 

 visible — and he backed out of the hole to dispose of the chips. He 

 ruffled his feathers considerably in squirming out backward, as his 

 body was a snug fit in the entrance hole. He threw out a quantity of 

 loose chips in this manner and then began chiseling, his tail mean- 

 while protruding from the doorway. He worked for 22 minutes; 

 then his mate came back. 



"She went inside and came out with her mouth quite full of chips; 

 but instead of tossing the chips to the ground, she flew off with them 

 to another tree. She stayed away for several minutes, then returned 

 and went to work in her accustomed way, staying within the cavity, 

 and thrusting only her head outside. Wlien she had worked about 

 15 minutes the male came again to the entrance. She put her head 



