e-tree. For at least seven days he had been thus occupied. Where
was his mate? On the edge of the wood, perhaps. But, if so, why did I
hear nothing from her, as I passed up and down? Again my hour and a half
had been spent to no purpose.

Not yet discouraged, I returned the next morning. For the three quarters
of an hour that I remained, the hummer was not once out of the ash-tree
for five minutes. I am not sure that he left it for five minutes
altogether. As usual, he perched almost without exception on one or
other of two dead limbs, while a similar branch, on the opposite side of
the trunk, he was never seen to touch. A Maryland yellow-throat alighted
on one of his two branches and began to sing, but had repeated his
strain only three or four times before the hummer, who had been absent
for the moment, darted upon him and put him to flight. A little
afterward, a red-eyed vireo alighted on his other favorite perch, and he
showed no resentment. The day before, a warbler had sat on the same
branch which the yellow-throat now invaded, and the hummer not only did
not offer to molest him, but flew away himself. These inconsistencies
made it hard to draw any inference from his behavior. During my whole
stay he did not once go to the apple-tree, although, for want of
anything better to do, I again scrutinized its branches. This time I
_was_ discouraged, and gave over the search. His secret, whatever it
might be, was "too dear for my possessing." But my fellow-observer kept
up his visits, as I have said, and the hummer remained faithful to his
task as late as July 15th, at least.

Some readers may be prompted to ask, as one of my correspondents asked
at the time, whether the mysterious sentry may not have been the mate of
our home bird. I see no ground for such a suspicion. The two places were
at least a mile apart, as I have already mentioned, and woods and hills,
to say nothing of the village, lay between. If he was our bird's mate,
his choice of a picket station was indeed an enigma. He might almost as
well have been on Mount Washington. Nor can I believe that he had any
connection with a nest found two months afterward in a pitch-pine grove
within a quarter of a mile, more or less, of his clearing. It was
undoubtedly a nest of that season, and might have been his for aught I
know, so far as the mere fact of distance was concerned; but here again
an intervening wood must have cut off all visual communication. If his
mate