appearance. The upper parts then are yellowish olive-green, sometimes with 

 faint streaks on the back. The deep-chestnut of the sides has given way to a few 

 spots or patches of this color. 



In seeking the Chestnut-sided Warbler, one should go to woodlands that have 

 been cut over and grown up in bushes. There are found the conditions which this 

 bird dearly loves, and in such a situation one may pass a whole forenoon and 

 seldom be out of sight or hearing of one or more of them. 



The nest is made of strips of bark, soft dead leaf-stems, and similar material ; 

 it is lined with tendrils and rootlets. Usually the nest is from two and a half 

 to three and a half feet from the ground. Rarely have I found one so situated 

 that it could not readily be reached by the spring of an agile house-cat, and there 

 is much evidence to show that many are pulled down every year by these feline 

 hunters. 



It is commonly reported that as many as five eggs are deposited in the nest 

 before the bird begins setting, but fully three-fourths of those nests that I have 

 found contained only four eggs. They are white, with numerous brown markings 

 of various shades — some distinct, others more or less obscure, as if the inside of 

 the shell had been painted and the color was showing through. The spots and 

 blotches are gathered chiefly in a wreath about the larger end. They are pretty, 

 dainty little objects, as is the case with all Warblers' eggs. In size, they are 

 about two-thirds of an inch long, and half an inch in diameter at the largest place. 



In the latitude of Boston, fresh eggs may usually be found late in May or in 

 the first week of June. 



The Chestnut-sided Warbler feeds almost exclusively on insects. John James 

 Audubon wrote that once in Pennsylvania, during a snow-storm in early spring, 

 he examined the dead bodies of several, and found that their stomachs contained 

 only grass-seeds and a few spiders. The birds were very poor, and evidently were 

 in a half-starved condition, which would probably account for the fact that they 

 had been engaged in such an un-warbler-like act as eating seeds. Ordinarily this 

 bird is highly insectivorous, and feeds very largely on leaf-eating caterpillars. It 

 also collects plant-lice, ants, leaf-hoppers, small bark-beetles, and, in fact, is a 

 perfect scourge to the small insect-life inhabiting the foliage of the bushes and 

 trees where it makes its home. Sometimes the birds take short flights in the air 

 after winged insects. It will thus be seen that the Chestnut-sided Warbler is of 

 decided value as a guardian of trees, which is reason enough why the legislators 

 of the various states where the bird is found were induced to enact the Audubon 

 Law for its protection. 



All birds that depend so much on insects for their livelihood as does the 

 Chestnut-sided Warbler are necessarily highly migratory. By the middle of Sep- 

 tember nearly all have departed from their summer home, which, we may say 

 roughly, covers the territory of the southern Canadian Provinces from Saskatche- 

 wan eastward, and extends southward as far as Ohio and New Jersey. They are 

 also found in summer along the Alleghany Mountains in Tennessee and South 

 Carolina. Most of the migrants go to Central America by way of the Gulf of 



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