“From the apple trees or shrubs near the house comes a cheerful lisping song that constantly declares that life up among the leaves is ‘Sweet-sweet-sweet-sweet-sweeter,’ ending this remark by a warble full of melody. Then a little bird smaller than a Chippy flits out with a bit of green worm hanging from his beak and disappears in another tree. Brief as the glimpse is, you see that the bird is rich olive-yellow, with cinnamon streaks on the breast. If he pauses a moment, you will notice that the underparts are almost the colour of gold. This is the _Yellow Warbler_ of many names,—_Wild Canary_, _Summer Yellowbird_, or simply _Yellowbird_; though this name is also commonly given to the seed-eating Goldfinch of the Sparrow tribe who wears a jaunty black cap, and stays with us all the year, while the Yellow Warbler goes southward before leaf-fall in September. “The Yellow Warbler’s nest is one of the most beautiful and interesting bird-homes, and shares the fame of that of the Baltimore Oriole, Wood Pewee, Humming-bird, and Vireo. It is cup-shaped and deep, woven of fibres and plant-down, and is placed in the fork of a bush or in a fruit tree, where it is as firmly lashed by cords of vegetable fibre and cobwebs. The female is the builder and a very rapid workwoman. This nest is often used by the Cowbird, but little Mrs. Yellow Warbler is more clever than many other small birds and refuses to be imposed upon. She is evidently afraid to push out the alien egg, so she swiftly walls it in by building a second nest on top of the first. If this does not check the Cowbird, a third nest is sometimes added, like the one that Tommy brought me last fall, and there is a two-story nest in Goldilocks’ cabinet. “This Warbler is not only beautiful to look at and pleasant to hear, but he is a very valuable tree trapper, for he eats the spinning cankerworms and also tent-caterpillars, pulling apart webs of the latter and using them ‘for cordage’ to bind the nest. He is also a destroyer of plant-lice and something of a flycatcher as well. _Maryland Yellowthroat_ “Here is a merry bird that you cannot miss seeing or fail to name if you have eyes and ears. Olive on head and back, this bird certainly has a yellow throat, also much yellow on tail, wings, and underparts, but if I had the naming of it I should call him the ‘Yellow, Black-masked Warbler,’ for he wears a narrow mask of black across his face, through which his keen eyes peer provokingly as he flits ahead calling for you to follow, ‘Follow me—follow me—follow!’ When you see the bird, of two points you may be sure at once; it is yellow, and it wears a black mask, but whether it is yellowest on back, throat, or breast will require a second look.