88 
BIRDS OF DURHAM AND VICINITY. 
the season, between the twentieth and twenty-fifth of May which 
might well be designated as " warbler week." Then, for a few days, 
the woods seem to be alive with them, and whoever will study warblers 
will miss his main chance if he is not in the woods at sunrise. Let 
him go along the eastern margin of low woods, keeping just outside, 
on grassland or in the highway where he can move about without 
making much noise, and the birds will conie to him to enjoy the 
warmth of the rising sun, and moreover to catch the insects that are 
active here before those deeper in the woods are astir. The few 
Bay-breasted Warblers tiiat I have seen were all discovered in the way 
I have just advocated. They have always been in company with other 
warblers, but I have never seen more than one at a time, 
Dendroica striata. Black-poll Warbler. 66i. 
Black-polls are common spring and fall migrants. The} come between 
the twentieth and the twenty-fifth of Ma} — that is, simultaneously 
with the Bay-breasted and Canadian Warblers, but they are far more 
abundant than either of the latter species. Spring migrants are oftener 
found in apple or maple trees on cultivated land, than in the woods. 
But in the fall I have usually seen them among gray birches and other 
more or less scattered pasture trees. I have found them here in 
autumn from August 31, until October 4. T!ie young birds have no 
black on the crown, and are sulTused above and below with a yellowish 
tinge, which renders them so unlike the adult male, the one usually 
seen in spring, that they are not leadily recognized. 
Dendroica blackburnise. Blackburnian Warbler. 662. 
In point of numbers, Blackburnian Warblers rank among the scarcer 
species but from the standpoint of beauty, none excel it. The males 
come first, and while they are often solitary, I have seen no less than 
six in the same tree at once. IVIy earliest record of this warbler's 
occurrence here in spring is the eleventh of May. As a rule they 
frequent evergreen woods, hemlocks and spruces preferred. They 
breed sparingly in the central portion of this state, and very probably 
do so here, though I have no data to this eftect. 
Dendroica virens. Black-throated Green Warbler. 667. 
There is still snow in the woods, and the leaves are still in bud, 
when the song of this common summer resident is first heard in the 
spring. Its earliest appearance that I have recorded was on the fifth 
