PRAIRIE WARBLER. 
243 
the Black-poll Warbler resembled the suppressed syllables 'tsh 
'tsh 'tsh 'tshea', beginning low, and gradually growing louder, 
having nearly the same slender whistle as that species, though 
somewhat stronger. The pair were busily engaged collecting 
flies and larva; from a clump of young locust-trees in the woods 
of Mount Auburn, and occasionally they flitted among the 
Virginian junipers ; the familiar visit of the male appeared for 
the purpose of discovering my intentions near the nest, about 
which he was naturally solicitous, though he made his ap- 
proaches with the appearance of accident. The female was 
more timid ; yet while I was still engaged in viewing this little 
interesting and secluded pair, she, without any precaution or 
concealment, went directly to the nest in the forks of a low 
barberry bush near by, and when there, she sat and looked at 
me some time before she removed. She made, however, no 
pretences to draw me away from the spot, where she was sit- 
ting on 4 eggs, of which I took away 2 ; her approaches to the 
nest were now more cautious, and she came escorted and en- 
couraged by the presence of her mate. Iwo eggs were again 
soon added, and the young brood, I believe, reared without 
any accident. 
The nest was scarcely distinguishable from that of the Sum- 
mer Yellow Bird, and quite different from the nests described 
by Wilson and Audubon. My opportunity for examination, 
so long continued, seemed to preclude the possibility of error 
in the investigation ; neither can I compare the slender note 
of this species to any whirring sound, which would more 
nearly approach to the song of the Pine Warbler. The Prairie 
Warbler visits Cambridge about the first or second week in 
May, and according to the observations of my friend Mr. 
Cooper, is seen probably about the same time in the vicinity 
of New York in small numbers and in pairs, and retires to 
winter in the West Indies about the middle of September. 
This species is now considered common in Massachusetts, 
though it has not been taken farther northward. It occurs m 
Ohio and in Michigan, but not in Ontario. It winters in south- 
ern Florida and the West Indies. 
