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 seen 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 Yireos 

 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 



Black and White Warblers, but in the meanwhile I will 



Warbler, mention only those species that can be 



Mniotuta varia. most easily observed. Among them is 



Plate LX. 



habit of creeping or climbing over trunk and limb aids 

 in his identification. He is a 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 



