186 USEFUL BIRDS. 



Mr. Robert H. Coleman, in a letter to the Biological Sur- 

 vey, stated, according to Dr. Judd, that he counted the 

 number of insects eaten by a Palm Warbler, and found that 

 it varied from forty to sixty per minute. The bird, he 

 said, spent at least four hours on his piazza, and in that time 

 must have eaten about nine thousand, five hundred insects. 



I have seen Warblers eating from masses of small insects 

 at such a rate that it was impossible for me to count the 

 number of insects eaten. When larger insects are taken, 

 the time given to each increases. The bird will sometimes 

 spend at least ten minutes in the attempt to swallow a 

 large caterpillar. It is difficult, therefore, to approximate the 

 number of insects eaten by a Warbler in a day, except where 

 it is feeding mainly on a particular species. 



In this family we find birds that assume the care of the 

 trees from the ground to the topmost twig. Some walk 

 daintily along the ground, searching among the shrubbery 

 and fallen leaves ; others cling close to the bark, and search 

 its every crevice for those insignificant insects which collect- 

 ively form the greatest pests of forest and orchard ; others 

 mount into the tree, skip from branch to branch, and peer 

 about among the leaves or search the opening buds of the 

 lower branches ; others habitually ascend to the tree tops ; 

 while still others are in almost constant pursuit of the winged 

 insects that dart about among the branches. We will first 

 consider the common ground-frequenting species. 



Northern Yellow-throat. Maryland Yellow-throat. 

 Geothlypis trichas brachidactyla. 



Length. About five and one-quarter inches. 



Adult Male. Upper parts olive-green ; forehead and mask black, bordered above 



by ashy-gray ; under parts mainly bright yellow. 



Adult Female. Like the male, but without the black or ashy ; under parts paler. 

 Nest. On or near the ground, supported by grass stems, leafy plants, or shrubs ; 



deep, and composed mainly of leaves and grasses; sometimes roofed, and 



not infrequently hair-lined. 



Eggs. White, spotted with brown and lilac at the larger end. 

 Season. May to October. 



This Yellow-throat is a bird of the brookside and swampy 

 thicket ; but it is not by any means confined to these locali- 

 ties, for it is found 'in the fruit garden and orchard as well as 



