"Why," cried Amy, "that little brown bird cannot be a robin."

"No," he answered, "that is my favorite of all the earliest birds--the
song-sparrow. You remember what Dr. Marvin said about him the other
evening? I have been looking for my little friend for a week past, and
here he is. The great tide of migration has turned northward."

"He is my favorite too," said his father. "Every spring for over seventy
years I remember hearing his song, and it is just as sweet and fresh to
me as ever. Indeed, it is enriched by a thousand memories."

For two or three days the robins continued plentiful around the house,
and their loud "military calls," as Burroughs describes them, were heard
at all hours from before the dawn into the dusk of night, but they seemed
to be too excited over their northward journey or their arrival at their
old haunts to indulge in the leisure of song. They reminded one of the
advent of an opera company. There was incessant chattering, a flitting to
and fro, bustle and excitement, each one having much to say, and no one
apparently stopping to listen. The majority undoubtedly continued their
migration, for the great flocks disappeared. It is said that the birds
that survive the vicissitudes of the year return to their former haunts,
and it would seem that they drop out of the general advance as they reach
the locality of the previous summer's nest, to which they are guided by
an unerring instinct.

The evening of the third day after their arrival was comparatively mild,
and the early twilight serene and quiet. The family were just sitting
down to supper when they heard a clear, mellow whistle, so resonant and
penetrating as to arrest their attention, although doors and windows were