WARBLERS. 
101 
soon as he sees you away he goes, and although you may hear 
him chuckling, he will not come in sight again. 
By the last of September the fall migration is under way and 
we begin to see strangers among our familiar birds. Again we 
see the dainty parula ,whose “ swinging retreat in the hanging 
moss ” is the most aesthetic of bird homes. With him the 
black-throated blue, and the aristocratic bay-breasted warbler. 
And some of our dearest local birds are preparing for flight. 
The little ones are grown up and ready to take their place in 
the bird world. The family life is merged in the life of the 
flock and we sadly realize our feathered friends will soon be 
gone. 
Olive Thorne Miller speaks of this strange episode in the life 
of all our warblers, this mysterious flitting called migration, as 
“ a subject of deep interest and at present very imperfectly under¬ 
stood. We know that the birds go, and where they go, and we 
can guess why they go ; but why they reverse the usual order 
of there lives and instead of going to sleep at dark, take that 
time to start off on a long journey , what route they take ; and 
who guides them over the hundreds or thousands of miles they 
travel, and brings them back next spring to the very tree they 
occupied the previous year; these things we do not know.” 
This month we may say with Longfellow : 
“ I hear the beat of their pinions fleet, 
As from the land of snow and sleet, 
They seek another lea; 
I hear the cry of their voices high 
Falling dreamily through the sky, 
But their forms I cannot see.” 
On the night of September 24, between half-past eight and 
ten o’clock, a large number of warblers passed over. Once in 
a while flitting forms could be observed, but the greater num¬ 
ber were too high to be seen. A few, the weaker ones probably, 
were flying quite low. That high-pitched, hissing whistle which 
is the distinctive warbler song type, could be regularly recog¬ 
nized. September 30, a flocked passed, but not so large as the 
one just mentioned. October 1, there was a notable increase 
