ow branch of
a maple by the roadside, where I had it under daily observation.
This nest presently held three eggs, two of which hatched in due
time, and for a few days the young seemed to prosper. Then one
morning, I noticed the mother bird sitting in a silent,
meditative way on the edge of the nest. As she made no move
during the minute or two while I watched her, I drew near to see
what was the matter. I found one of the young birds in a state of
utter collapse; it was cold and all but lifeless. The next
morning I found the bird again sitting motionless on the rim of
the nest and gazing into it. I found one of the birds dead and
the other nearly so. What had brought about the disaster I could
not tell; no cause was apparent. I at first suspected vermin, but
could detect none. The silent, baffled look of the mother bird I
shall not soon forget. There was no demonstration of grief or
alarm; only a brooding, puzzled look.

I once witnessed similar behavior on the part of a pair of
bluebirds that were rearing a brood in a box on a grape post near
my study. One day I chanced to observe one of the parent birds at
the entrance of the nest, gazing long and intently in. In the
course of the day I saw this act several times, and in no case
did the bird enter the box with food as it had been doing. Then I
investigated and found the nearly fledged birds all dead. On
removing them I found the nest infested with many dark,
tough-skinned, very active worms or grubs nearly an inch long,
that had apparently sucked the blood out of the bodies of the
fledglings. They were probably the larvae of some species of
beetle unknown to me. The parent birds had looked on and seen
their young destroyed, and made no effort to free the nest of
their enemy. Or probably they had not suspected what was going
on, or did not understand it if they beheld it. Their instincts
were not on the alert for an enemy so subtle, and one springing
up in the nest itself. Any visible danger from without alarmed
them instantly, but here was a new foe that doubtless they had
never before had to cope with.

The oriole in her nest-building seems more fickle than most other
birds. I have known orioles several times to begin a nest and
then leave it and go elsewhere. Last year one started a nest in
an oak near my study, then after a few days of hesitating labor
left it and selected the traditional site of her race, the
pendent branch of an elm by the roadside. This ti