July
being able to further test the reliability of my system. Having watched him for some time and convinced myself that the birch tree was really the favored one (although there was a tall hemlock with dead branches also not far off, which was almost equally used). I proceeded to measure off the prescribed distance as already indicated. This being done and the ground, which was truly a warbler one, inspected. I noticed that on the eastern side the trees were taller than the birch or 'singing tree,' and therefore the latter did not dominate this part of the circle, and in all probability the nest would not be there. In passing, it may be well to mention that the singing tree does not always necessarily dominate the nesting one, although I have generally found it to do so, an exception being that of a male Purple Finch (Carpodacus purpureus purpureus) who sang from an apple tree on the opposite side of the spruce tree in which the nest was placed, but in this case there were no trees overlooking the nest at all. Surely the male had no voice in selecting that site (although he undoubtedly did the 'singing tree,' as he had frequented it often previous to any rest being started in the spruce), invisible as it was to him whilst singing! But there, that opens up another interesting problem, and I must get back to the work in hand. After watching the male Bay-breast for some time. I noticed that he generally faced either north or south, whilst in the two singing trees,' more generally the latter, and I concluded that somewhere in that direction the nest would eventually be found, as it was an absolutely ideal spot. Now in the lower branches of the hemlock tree a male Magnolia Warbler ventured to sing on several occasions, but was always driven away by the Bay-breasted Warbler. This looked suspicious and I overhauled the firs and spruces in close proximity, with the result that the female Magnolia was flushed from her nest and set of four eggs only seven yards away from where the male had attempted to sing.
Time was flying fast, however, and still no signs of the female Bay-breasted Warbler, until a sudden downward swoop of the male to the south, brought her out to the east, and I was able to follow her about for a short time, until she eventually gave me the slip. Then I began to search the southern site more carefully, from which direction I had also just previously heard some Thrush-like
