(and correspondingly lucid) explanation.

[23] While this book is passing through the press (April 30th, 1885) I
am privileged with another sight and sound of the woodcock's vespertine
performance, and under peculiarly favorable conditions. In the account
given above, sufficient distinction is not made between the clicking
noise, heard while the bird is soaring, and the sounds which signalize
his descent. The former is probably produced by the wings, although I
have heretofore thought otherwise, while the latter are certainly vocal,
and no doubt intended as a song. But they are little if at all louder
than the _click, click_ of the wings, and as far as I have ever been
able to make out are nothing more than a series of quick, breathless
whistles, with no attempt at either melody or rhythm.

In the present instance I could see only the start and the "finish,"
when the bird several times passed directly by and over me, as I stood
in a cluster of low birches, within two or three rods of his point of
departure. His angle of flight was small; quite as if he had been going
and coming from one field to another, in the ordinary course. Once I
timed him, and found that he was on the wing for a few seconds more than
a minute.

[24] Still further to corroborate my "pet theory," I may say here in a
foot-note, what I have said elsewhere with more detail, that before the
end of the following month the hermit thrushes, the olive-backed
thrushes, and the gray-cheeked thrushes all sang for me in my Melrose
woods.

Let me explain, also, that when I call the brown creeper a silent
migrant I am not unaware that others beside myself, and more than
myself, have heard him sing while traveling. Mr. William Brewster, as
quoted by Dr. Brewer in the _History of North American Birds_, has been
exceptionally fortunate in this regard. But my expression is correct as
far as the rule is concerned; and the latest word upon the subject which
has come under my eye is this from Mr. E. P. Bicknell's "Study of the
Singing of our Birds," in _The Auk_ for April, 1884: "Some feeble notes,
suggestive of those of _Regulus satrapa_, are this bird's usual
utterance during its visit. Its song I have never heard."

AN OWL'S HEAD HOLIDAY.

Let Euclid rest, and Archimedes pause,
And what the Swede intends, and what the French.

MILTON.

AN OWL'S HEAD