84 IN BIRD LAND. 
That the army of migrants travel mostly by night 
is a well-known fact that can be verified by any one 
who will stand out-of-doors and listen to their chirp- 
ing overhead. ‘They seem to move in loose flocks, 
for there are intervals of complete silence, followed 
by a promiscuous chirping from many throats. Nor 
are these nocturnal calls all uttered by a single 
species, but usually a number of species seem to be 
travelling in company. One might say, therefore, 
that the feathered army moves in squads. As they 
travel in the dark, very little can be said about their 
flight ; but every student has found species of birds 
in an early morning ramble which he could not find 
anywhere on the previous day, proving that they must 
have arrived in the night. Here is a single excerpt 
—many might be given — from my note-book: “ On 
the third of March, 1894, I took a long stroll into the 
country, remaining in the fields until dusk; not a 
single meadow-lark was to be seen or heard. At 
daybreak next morning, however, the shrill whistle 
of I know not how many larks rose like musical 
incense from the fields and commons in the rear of 
my house. Depend upon it, had these lavish min- 
strels been in the neighborhood during the previous 
afternoon, they would not have escaped my atten- 
tion, for they could not have kept their music in 
their larynxes, not they! ‘There is a cog in Nature’s 
machinery lost if the meadow-larks are silent for 
a half day in the spring.” 
In 1885 Mr. William Brewster, the well-known 
ornithologist, made some imtensely interesting dis- 
