204 



VIREONID^E : GREENLETS. 



Massachusetts has been thought to form the ex- 

 treme southern limit of the Blue-headed Greenlet in 

 the breeding season, but this view does not prove 

 to hold good, as the bird breeds in Connecticut, and 

 even in the Middle StateSc In southern New Eng- 

 land, however, this Vireo is chiefly a migrant in spring 

 and fall, passing on into the Canadian Fauna to breed 

 in greater abundance there than in the Alleghanian. 

 It is one of the three commoner Vireos of northern 

 New England in summer, the Yellow-throated and 

 the White-eyed being more restricted in their re- 

 spective ranges, 

 and the Phila- 

 delphian for the 

 most part pass- 

 ing unnoticed. It 

 arrives in New 

 England earlier 

 than the other 

 Vireos, being sometimes seen in Massachusetts in the 

 last week of April, and likewise lingers later in the 

 fall all through September, and occasionally until 

 the middle of October. Nests have been found in Con- 

 necticut and Massachusetts as well as farther north, 

 but the bird seems to be nowhere very prominent in 

 the composition of the Avifauna. It is scarcely an 

 inhabitant of the streets and parks like the Red-eyed 

 or Warbling Greenlet, preferring the solitude of the 

 woods ; and hence less frequently comes under obser- 

 vation. The nest is described as resembling that of 

 trje Yellow-throated Greenlet, being composed chiefly 

 of bark-strips, fine grasses, and rootlets, ornamented 

 with mosses and lichens. The eggs are undistinguish- 



FIG. 51. DETAILS OF STRUCTURE OF BLUE-HEADED 

 GREENLET. (Natural size.) 



