400 BULLETIN 17 6, UNITED STATES NATIONAL MUSEUM 



that each pair raises at least two broods during the spring and 

 summer." 



Eggs. — Two eggs almost invariably make up the full set for the 

 rufous hummer, but Major Bendire (1895) records a set of three, 

 taken by Clyde L. Kellar, of Salem, Oreg. D, E. Brown tells me 

 that often there is only one, and he has "seen one nest that contained 

 four, evidently contributed by two females." The eggs are like other 

 hummingbirds' eggs, dead pure white and varying from oval to ellip- 

 tical-oval in shape. The measurements of 53 eggs average 13.1 by 

 8.8 millimeters ; the eggs showing the four extremes measure 14.0 by 

 8.7, 13.1 by 10.0, 11.4 by 8.9, and 13.0 by 7.7 millimeters. 



Young. — The period of incubation is said to be 12 days (Burns, 

 1921), but probably it is nearer 13 or 14 days, as with some other 

 hummingbirds. This duty and the care of the young are performed 

 entirely by the female; the male seldom, if ever, comes near the nest 

 after the eggs are laid. William L. Finley (1905) writes: 



As soon as the cottony cup was finished and the mother had cradled her 

 twin white eggs, the father disappeared. He merely dropped out of existence, 

 as Bradford Torrey says, leaving a widow with twins on her hands. This 

 generally seems to be the case, for at the different nests where I have watched, 

 I never but once saw a male hummer near the nest after the young were 

 hatched. I was lying in the shade of the bushes a few feet from the nest one 

 afternoon. For two whole days, I had been watching and photographing and 

 no other hummer had been near. Suddenly a male darted up the canyon and 

 lit on a dead twig opposite the nest. He hadn't settled before the mother 

 hurtled at him. I jumped up to watch. They shot up and down the hillside 

 like winged bullets, through trees and over stumps, the mother, with tail 

 spread and all the while squeaking like mad. It looked like the chase of two 

 meteors, that were likely to disappear in a shower of sparks, had they struck 

 anything. If it was the father, he didn't get a squint at the bantlings. If it 

 was a bachelor a-wooing, he got a hot reception. 



On the other hand, Alfred M. Bailey (1927) saw, in southeastern 

 Alaska, an adult male incubating on a set of eggs nearly ready to 

 hatch, of which he says: "I was walking along the base of a pre- 

 cipitous cliff when I noticed the handsome little male hovering over 

 my head, about twenty feet up, and v/as then surprised to see him 

 climb into a nest, in the terminal branches of a drooping spruce. 

 ^Vlien incubating, the little male squatted far down in the nest, with 

 tail and beak pointed almost vertically, and he proved so tame that 

 1 believe I could have touched him." 



The following statements are based on, and the quotations are 

 taken from, some elaborate notes sent to me by A. Dawes DuBois, 

 who made an intensive study of a nest of the rufous hummingbird 

 near Belton, Mont. In order to be able to study the parent and the 

 single young bird at close range, he concealed himself in a "balsam 

 cloak," which was "prepared by sewing balsam boughs all over the 



