414 BULLETIN 17 6, UNITED STATES NATIONAL MUSEUM 



used in cleaning harnesses, and about 5 feet from the ground ; broods 

 were raised in the first two, but the third was abandoned. 



W. L. Dawson (1923) writes: "As for the Allen Hammer the black- 

 berry tangles are her home, and all such other situations as assure a 

 measure of protection from above. Thus, drooping vines falling over 

 boulders offer ideal sites ; for alleni is also fond of a swing. The most 

 remarkable nest of our experience, a five-story one, was saddled upon 

 the hook of a broken root, which was, in turn, caught upon a sprangle 

 of roots above, unearthed by the under-cutting of the stream. This 

 root could be lifted clear and replaced without injury; and its mis- 

 tress added, in one season, stories No. 4 and No. 5, to our knowledge." 



Two of the four nests of Allen's hummingbird in the Thayer col- 

 lection in Cambridge are large handsome nests, suggesting the best 

 types of nests of the rufous hummingbird. One of these was 8 feet 

 from the ground and 20 feet out from the trunk on a branch of a 

 spruce; it is composed of fine green moss, decorated with flakes of 

 pale-gray lichens, bound on with spider web, and lined with willow 

 cotton; it measures approximately 2 inches wide and 1 inch high 

 externally ; the inner cup is about 1 inch in diameter by five-eighths 

 of an inch deep. The other large nest was built on a branch of a 

 young live oak between upright twigs; it measures about 2 inches 

 in diameter and 1% inches in height externally; it appears to be 

 made almost entirely, including all the rim, of the pale buff cot- 

 tony down from willow blossoms ; only the lower and external part ol 

 the nest is composed of green mosses and various brown fibers; it is 

 a very pretty nest. The smallest nest in the lot was 2 feet from the 

 ground in a shallow bend of a horizontal branch of a sagebrush; it 

 measures 1% by 1^4 inches in external diameter, and is only three- 

 quarters of an inch high, the inner cavity being very shallow; this 

 is a very drab-looking nest, with no green moss in its composition; 

 it is made of various gray and brown fibers and similar material, with 

 very little cotton and a few small feathers in the lining ; apparently it 

 matched its surroundings in the gray sage. 



Since the above was written Ernest I. Dyer (1939) has published 

 a detailed account of the nesting of Allen's hummingbird, to which 

 the reader is referred. 



Eggs. — Allen's hummingbird lays almost invariably two eggs; I 

 have no record of more or fewer. They are like other hummers' eggs, 

 varying in shape from oval to elliptical-oval, and are pure white 

 without gloss. The measurements of 55 eggs average 12.7 by 8.6 mil- 

 limeters ; the eggs showing the four extremes measure 14.0 by 8.9, 13.8 

 by 10.0, and 11.7 by 7.6 millimeters. 



Toung. — The incubation period of this hummingbird is said to be 

 14: or 15 days, as is the case with several other hummingbirds. The 



