Cambridge, Mass.
1911.
Sept.8
[September 8, 1911]

  Cloudy & cool with chill easterly wind. Very cool last night.

Two Wilson's Black cap Warblers in our Garden
Black-polls & Redstart.

  In our Garden this morning I found, in a
thicket in the jungle, a [male] Wilson's Black-cap having a nearly full
black cap. It chirped so nearly like a Maryland Yellow-throat that had
I not seen it plainly, within a few yards, I should have set it down
quite confidently as a representation of that species. Not long before
sunset I heard again the yellow-throat-like tchay and traced it
to a black-capped Wilsonia pusilla, no doubt the same bird seen earlier
in the day but now accompanied by a [female] with a plain olive green
crown & bright yellow underparts. The two were at first among
some sun flower plants in the flower gardens but they soon flew up
into a grey birch where they joined two Black-poll warblers & an adult [male]
Red-start with which they spent the next fifteen or twenty minutes,
actively foraging for food in their usual characteristic manner. It was
easy to distinguish them from the others by their short, jerky upward
sallies on wing after insects flying or on the under sides of the leaves
and by the peculiar way in which they lifted & depressed their long tails.