BLACKBURNIAN WARBLER 341 



Pa., were in hemlocks, "at elevations varying from twenty to fifty feet. 

 The exceptional nest was in a large chestnut, sixty feet from the 

 ground." 



Dr. Roberts (1936) mentions a Minnesota nest "situated in an arbor 

 vitae tree, directly over the entrance to a cabin," and one "placed in 

 a small spruce, close to the trunk, about 2 feet from the top of the 

 tree and about 20 feet from the ground. Another was found in "a 

 jack-pine tree, 20 feet from the gi-ound, 6 feet from the trunk, resting 

 in a tangle of small branches, and concealed by a closely overhanging 

 branch." 



Eggs. — The Blackburnian warbler lays normally 4 or 5 eggs, usually 

 4; in a series of 14 sets there are only 3 sets of 5. They are ovate to 

 short ovate and slightly glossy. The ground color is snowy white 

 or very pale greenish white, and is handsomely spotted and blotched 

 with "auburn," "bay," "argus brown," "Mars brown," or "mummy 

 brown," with undertones of "brownish drab," or "light vinaceous- 

 drab." On some eggs the clrab marks are the most prevalent, with 

 fewer but more prominent spots or blotches of dark brown shades, 

 such as "Mars brown" and "mummy brown." Others have spots of 

 "auburn" and "bay" so concentrated that they form a solid band 

 around the large end. In addition a few small scrawls of brownish 

 black are often found. Generally speaking the markings tend to form 

 a wreath, but some eggs are spotted more or less evenly all over the 

 surface. The measurements of 50 eggs average 17.2 by 12.8 milli- 

 meters; the eggs showing the four extremes measure 18.0 by 13.6, 

 17.0 by 13.7, 15.6 by 12.5, and 17.1 by 12.0 millimeters (Harris). 



Young. — We have no information on incubation and very little on 

 the care of the young. The male has been seen to go onto the nest, 

 and evidently shares occasionally in the duty of incubation. Both 

 parents help in feeding the young, as noted by Mrs. Nice (1932) at 

 the nest she was watching. When Mrs. Nice's daughter climbed a 

 tree near the nest, the female "assumed a peculiar attitude, her tail 

 outspread and dropped at right angles to her body, her wings flipping 

 rapidly and occasionally held stiffly up or down. The excitement 

 caused the young to jump out on the ground where they could not be 

 found." 



Plumages. — Dr. D wight (1900) calls the natal down sepia-brown, 

 and in speaking of the males, describes the juvenal plumage as "above, 

 dark sepia-brown obscurely streaked on the back with clove-brown. 

 Wings and tail clove-brown edged with olive-buff, the tertiaries and 

 coverts with white forming two wing bands at tips of greater and 

 median coverts ; the outer three rectrices largely white. Below, white, 

 washed with wood brown or buff on breast and sides, spotted, except 

 on chin, abdomen and crissum, with dull sepia. Superciliary stripe 



981873—53 23 



