328 BULLETIN 17 6, UNITED STATES NATIONAL MUSEUM 



very frequently both parents feeding among the flowers and occasionally within 

 arm's length of me. * * * 



During the last few days of my previous visit, I had seen the female In a 

 bunkhouse that had formerly been used as a greenhouse. A piece of baling 

 wire was wound around a nail in a rafter and formed a sort of hook. When 

 I found the young one gone, I went at once to this bunkhouse and found the 

 female sitting on a completed nest. She flew as I entered the room. I secured 

 a ladder and soon held the nest and two fresh eggs in my hand. Some chil- 

 dren were occupying this room so I did not dare leave the nest for further 

 notes. I put another wire up, however, to furnish another nesting site. 



June 21, the nest where the young had been seemed to be receiving additions, 

 and the sides were somewhat built up, but I could not see the birds around. 

 June 25 the nest contained one egg and the next morning there were two. A 

 visitor told me that it was liable to be taken by some small boys who were 

 there, so again I was afraid to leave it for observation and collected the nest 

 and set, flrst taking a picture of it, showing the eggs. * * * 



The nest is made largely of oak blossom hulls, and stems of the same, with 

 a small amount of plant down intermixed. The whole is well tied together 

 with cobwebs. The nest cavity is shallow and the edges are not incurved, 

 differing in both these respects from the nests of other hummingbirds with 

 which I am familiar. 



There is a nest, with a set of two eggs, of this hummer in the 

 Thayer collection in Cambridge that was taken by Mr. Willard in 

 the same locality on May 31, 1913. It was placed "on a wire hanging 

 from the ceiling of an old barn; this pair had already raised one 

 brood of young this season." It is a large and roughly made nest, 

 nearly 3 inches high by 2% inches in diameter and the inner cavity 

 nearly an inch deep. It is made of a great variety of plant material, 

 as described above, felted closely into a compact structure, reinforced 

 with coarse straws and weed stems, bound together with fine fibers 

 and cobwebs, and lined with finer pieces of similar material. The 

 material used reminds me of the kind used in bushtits' nests. Similar 

 materials were used in the nest we found in the Mimulus cardinalis, 

 referred to above. 



Milton S. and Kose Carolyn Kay (1925) found a nest in a narrow 

 canyon in the Huachuca Mountains on May 28, 1924. It was "sus- 

 pended on a wire hanging from one of the rafters" in a small de- 

 serted building. Mr. Ray says of it : "The nest is beautifully woven of 

 moss, plant down and cottony fibers, webbed together on the ex- 

 terior and decorated there with bits of very bright green moss and 

 pale green lichens. The lining of the nest consists almost entirely of 

 cottony fibers and down. It is unusually large for a hummingbird, 

 measuring 3^4 inches high by 2% across. The cavity is 1% across by 

 1% deep." 



Eggs. — The Arizona blue-throated hummingbird lays either one or 

 two eggs, normally two. These are like other hummers' eggs, ellip- 

 tical-oval, pure white, and without gloss. The measurements of eight 

 eggs average 15.1 by 10.0 millimeters; the eggs showing the four 



