BLACK AND WHITE WARBLER. 167 
and their lisping notes blend with other woodland voices 
without attracting our attention. 
May and September are the months for Warblers. 
Some species arrive in April, but they are most numer- 
ous between May 5 and 15, when the woods are 
thronged with their flitting forms. Less than half of our 
thirty-five species remain to breed; the others go to their 
summer homes in the coniferous forests of the North. 
These northern birds return in the latter part of August 
and abound in September. Many of the Warblers seen 
at this season are immature birds wearing plumages so 
different from those of the adult birds scen in the spring, 
that their identity is not suspected, and, in effect, they 
are new birds to us. 
To the field ornithologist Warblers are therefore the 
most difficult as well as the most fascinating birds to 
study. Long after the Sparrows, Flycatchers, and Vireos 
have been mastered, there will be unsolved problems 
among the Warblers. Some rare species will be left to 
look for—it may be a member of the band flitting about 
actively in the branches above us—and in the hope of 
finding it we eagerly examine bird after bird until our 
enthusiasm yields to an aching neck. 
Acquaintance with more familiar birds will doubtless 
arouse the enthusiasm necessary to a successful pursuit of 
ek ns Whites Warblers, but in the meanwhile I will 
Warbler, Mention only those species that can be 
Mniotilta varia. most easily observed. Among them is 
rae LK. the Black and White Warbler, whose 
habit of creeping or climbing over trunk and limb aids 
in his identification. He isa summer resident, and about 
April 20 we may expect to hear the thin, wiry see-see- 
see-see notes which form his song. A month later we 
may find his nest, placed on the ground at the base of 
a stump or stone and containing four or five white 
