198 USEFUL BIRDS. 



the tree insects which it pursues unless they reach the upper 

 air, where the Redstart seldom goes, except in migration. 

 It has been named the flycatcher of the inner tree tops, but 

 it is a flycatcher of the bush tops as well. While there are 

 few small pests of deciduous trees that it does not eat in 

 some form, it is not confined to these trees, but forages more 

 or less among coniferous trees. Also it is seen at times in 

 orchards, and gleans among shade trees in localities where 

 the woods are cut away. It is impossible to weigh the pros 

 and cons of this bird's food, for no thorough examination of 

 it has ever been made. It is an efficient caterpillar hunter, 

 and one of the most destructive enemies of the smaller hairy 

 caterpillars. It catches bugs, moths, gnats, two-winged flies, 

 small grasshoppers, and beetles. It probably secures a larger 

 proportion of parasitic hymenoptera and diptera than most 

 other Warblers, occasionally destroying a few wasps ; other- 

 wise, its habits seem to be entirely beneficial. 



Black-throated Green Warbler. 



Dendroica virens. 

 Length. About five inches. 

 Adult Male. Olive above; sides of head and neck yellow, often with darker 



line through eye ; chin, throat, and breast black ; belly white ; sides striped 



with blackish ; wings and tail dark ; white wing bars ; outer tail feathers 



marked with white. 



Adult Female. Yellow duller ; black of throat largely obscured by gray. 

 Nest. Usually fifteen to fifty feet up in a white pine, in a fork toward the end 



of a branch ; made of bark, twigs, and grasses, and lined with soft materials. 

 Eggs. Creamy white, with brown and purplish markings grouped toward the 



larger end. 

 Season. April to October. 



The Warblers noted in the pages immediately preceding 

 live largely among deciduous trees and shrubbery ; but 

 this species dwells by choice among coniferous trees, and 

 in Massachusetts it stays principally in groves of white 

 pine. While migrating in spring and fall it feeds anywhere 

 in mixed deciduous woods, but it is evidently more at home 

 among the pines, where it gleans its usual food from the 

 lower branches to the tree tops. This bird does not com- 

 monly descend to the ground except to procure nesting 

 material or to bathe. 



