In the roadside treesall freshly planted, like the citywere myrtle warblers, prairie warblers, and blue yellowbacks, the two latter in song.

In the same pine woods, too, there was much good music: house wrens, Carolina wrens, red-eyed and white-eyed vireos, pine warblers, yellow-throated warblers, blue yellowbacks, red-eyed chewinks, and, twice welcome, like the bluebirds, a Carolina chickadee.

" Mr. Van Kamp took a wad of loose bills from his trousers pocket, straightened them out leisurely, and placed them in his bill book, along with some smooth yellowbacks of eye-bulging denominations.

In literature we have to differentiate what is purely a commercial product like the yellowback novel, what is educational like the classic, and what is of the new.

Hum! Sounds like one of those old yellowback novels," remarked Mr. Blake, with a smile.