Cambridge, Mass.
May I
  Clear and cool with strong N.W. wind.
  Most of last night was very warm but the weather
changed & became much cooler at some time not
long before day-break. A small flight of migrants
came with the close of the warm wave for I found
in the Garden this morning a male Yellow Warbler, male & female Black
and White Creeper, a male Towhee and a Brown Thrasher besides
the Solitary Vireo that has been here since the 28th April.
I watched and listened for Chimney Swifts last evening
but in vain. It looks now as if the late April and early
May migrants are likely to be a little later than usual
rather than the reverse. The vegetation made a great
advance on April 29th & 30th and is now considerably
ahead of that of average seasons. Our lilac bushes are in
nearly full leaf, the pear trees in full bloom and a 
few apple blossoms unfolded.
  The Solitary Vireo in the garden was singing both songs
again this morning & again both were absolutely typical. During
the time I spent watching it it kept to the flavifrons song
for one minute, then changed to the solitarius song which it
used for one and a half minutes, next gave the flavifrons
song for half a minute and finally the solitarius song for
half a minute. The intervals of silence between these songs
were brief - from a few seconds to half a minute - but in
every instance they were well-marked.
Solitary Vireo with two songs.