BLACK-THROATED BLUE WARBLER 137 



It was on a high bluff covered with spruce timber and with but little 

 underbrush and was placed in the top of an overturned and dead 

 spruce about eighteen inches from the ground. On June 13, it con- 

 tained three eggs which hatched on the next day. I never found 

 another nest in the spruce timber and I never found another in open 

 woods, that is, free from underbrush, nor in any location corres- 

 ponding to this dead tree-top. After several years searching with 

 some success, I think it is safe to say that this species builds in hard- 

 wood forests, where the large timber stands somewhat openly, but 

 where all space is grown up with dense undergrowth of hardwood 

 saplings and brush with large leaves. I also think that the breeding 

 spots are very local, and that one may pass through many miles 

 of forest and not find a pair of these birds ; but when just the right 

 kind of hardwood knoll is found, several pairs may be looked for 

 within a short distance. My facts are rather meagre for this deduc- 

 tion, but this is my belief." (Bagg, MS.) 



At Branchport, N. Y., Burtch says that this species is "a rare 

 but regular summer resident. It may be found in the mixed growths 

 of oaks, maple, beech, chestnut and hemlock where the undergrowth 

 is quite thick." (Burtch, MS.) 



The first known nest of the Black-throated Blue Warbler was 

 discovered by John Burroughs^ early in July, 187 1, at Roxbury, Dela- 

 ware County, N. Y. It contained four fle'dged young and one egg. 

 The latter, with the nest, is described by Brewer (B. B. and R., 

 History of N. A. Birds, I, 257) while in 'Locusts and Wild Honey' 

 Burroughs gives a description of the hunt for the nest which could 

 have been written only by a born birds' nester. 



Song. — "There is not a more regularly and amply versatile 

 singer among our eastern Warblers than the Black-throated Blue. It 

 has at least four main songs, on which it is forever playing notable 

 variations. Of these four, two end on a sharply-ascending scale, and 

 two are almost monotones. Zwee swee swee, is a book rendering, and 

 a fairly good one, of the commoner monotone song. The other, of 

 two notes only, has almost the form and emphasis of the Blue-winged 

 Warbler's explosive little shorter song, Swee-chirrrr ! , but is louder 

 and somewhat more languid, with the characteristic and unmistak- 

 able full-voiced huskiness of the Black-throated Blue. It might be 

 syllabled Wher weeeee. The second half, in addition to being more 

 emphatic, is a little bit lower in key. Of the other two songs, the 

 commoner one is like the syllables Wheer, wheer, ivheeee, — rather 

 deliberately uttered, — the first two notes almost alike, the final drawled 



