ow early in the season does this nightly flocking begin? This question
often presented itself. It was only the middle of July when the
Cambridge roost was found in full operation, though at that time many
robins must still have had family duties, and some were probably
building new nests. Next summer, we said, we would try to mark the
beginnings of the congregation.

My own plans to this end came near being thwarted. In December I was
dismayed to see the owner of the wood cutting it down. Happily some kind
power stayed his hand when not more than a third of the mischief was
done, and on the 29th of June, 1890, while strolling homeward along the
highway, listening to the distant song of a veery, I noticed within five
or ten minutes seventeen robins making toward the old rendezvous. On
the following evening I stood beside the ice-pond and saw one hundred
and ninety-two robins enter the wood. The flight had begun before my
arrival, and was not entirely over when I came away. Evidently several
hundreds of the birds were already passing their nights in company. In
my ignorance, I was surprised at the early date; but when I communicated
my discovery to the Belmont observer, he replied at once that he had
noticed a movement of the same kind on the 11th of June. The birds,
about a dozen, were seen passing his house.

Thinking over the matter, I began to ask myself--though I hesitate about
making such a confession--whether it might not be the adult males who
thus unseasonably went off to bed in a crowd, leaving their mates to
care for eggs and little ones. At this very moment, as it happened, I
was watching with lively sympathy the incessant activities of a female
humming-bird, who appeared to be bringing up a family (two very hungry
nestlings), with no husband to lift a finger for her assistance; and the
sight, as I fear, put me into a cynical mood. Male robins were probably
like males in general,--lovers of clubs and shirkers of home duties.
Indeed, a friend who went into the roost with me, one evening, remarked
upon the continual cackling in the treetops as "a very social sound;"
and upon my saying something about a sewing circle, he answered, quite
seriously, "No, it is rather like a gentleman's club." But it would have
been unscientific, as well as unchristian, to entertain an hypothesis
like this without putting its soundness to some kind of test. I adopted
the only plan that occurred to me,--short of rising at half past t