264 BULLETIN 2 03, UNITED STATES NATIONAL MUSEUM 



J. Stuart Rowley writes to me : "In California, I have found sev- 

 eral nests of this species in the San Bernardino Mountains and in the 

 Mono Countj^ area in the northern part of the State. The nests I have 

 found have all been beautifully made structures, securely fastened 

 to small, low hanging branches of lodgpole pine, and placed about 10 

 to 12 feet from the ground." 



Dr. Grinnell (1908) records three nests, found in the San Bernar- 

 dinos ; one "was twenty feet above the ground in the thick foliage of 

 a short drooping fir bough. It was compactly composed of weathered 

 grasses, frayed-out plant fibres, and tail and wing feathers of j uncos 

 and other small birds. Internally it was thickly lined with mountain 

 quail feathers, some of the chestnut-colored ones sticking above the 

 rim conspicuously. This feather feature seems to be characteristic of 

 Audubon warblers' nests, as it was noticeably present in all that we 

 saw." Another nest was 25 feet from the ground in one of the lowest 

 branches of a yellow pine. The third "was snugly tucked away in a 

 small clump of mistletoe on an alder branch twelve feet above the 

 ground." 



J. K. Jensen (1923) says of New Mexico nests: "The nests are usu- 

 ally placed on a horizontal limb of a pine or spruce, but also among 

 dead twigs on the trunks of cottonwoods, and even in a cavity of some 

 tree. All nests found were lined with a few feathers of Bluebirds and 

 Long-crested Jay." 



Nests in tamarack, cedar, and birch have been reported by other 

 collectors. 



Eggs. — Audubon's w^arbler lays from 3 to 5 eggs, almost always 4. 

 They are ovate, tending toward short ovate, and are slightly glossy. 

 They are grayish or creamy white, spotted and blotched with "raw 

 umber," "Brussels brown," "argus brown," and sometimes "auburn," 

 with underlying spots of "pale brownish drab," "light brownish drab," 

 or "light mouse gray." The markings are often confined to the large 

 end, and frequently the drab undertones are in the majority, some- 

 times running together to form a cap, and this is relieved with a few 

 superimposed spots or blotches of dark "argus brown," or scattered 

 small scrawls so dark as to appear almost black. The eggs generally 

 are sparsely but rather boldly marked. The measurements of 50 eggs 

 average 17.6 by 13.5 millimeters; the eggs showing the four extremes 

 measure 19.4 by 14.0, 19.1 by 14.5, and 15.4 by 12.3 millimeters (Harris) . 



Young. — The period of incubation is probably between 12 and 13 

 days, as with the Myrtle warbler. Mrs. Wheelock (1904) writes : 



In the brood whose incubation was closely watched, I found that twelve days 

 elapsed between the laying of the last egg and the advent of the young. The 

 female did most of the brooding ; the male was found on the nest only once, but 

 was usually perched on a neighboring tree warbling his enthusiastic little 

 song, "cheree-cheree-cheree-cheree." After the young were feathered enough to 



