That day I found the first nest of the prothonotary warbler. This bird uses deserted woodpeckers' nests in dead trees set in marshes, so it was necessary to paddle around to every dead tree which showed a hole. I finally saw a little red-birch stub sticking up in the corner of the marsh, and rowing over to it, noticed a small hole in its side. Picking away the bark, I made it larger and a piece of the fresh green moss, from which the nest of the prothonotary warbler is always built, showed itself. Imbedded in the moss was a vivid orange-yellow feather, which could belong to no other bird. The nest was just built and contained no eggs. The Banker found the second nest, in a willow-stub ten feet from the ground, in an old downy woodpecker's nest. He found it by seeing the male bird fly into the hole. Climbing up to the nest, he found that in it were four young birds. Perching on a limb, he sat about four feet from the nest while I was in the boat perhaps ten feet away. The cock-bird flew up with a May-fly, making a soft alarm-note something like that made by a field sparrow, only gentler. He flew up close to where my friend sat and hesitated for a long while. Finally, the hungry little birds inside gave a prolonged squeak, which probably meant, "May-flies immediately!" This was too much for Mr. Prothonotary. With a farewell look at the Banker, he turned his back and dived into the nest, placing himself entirely at the mercy of this giant who was keeping guard over his home. Seven times he did this while we watched, bringing in two beetles, a small wasp, a fly, and three May-flies. The hen-bird would come up time and time again with a fly in her beak, but never could quite muster up courage enough to go into the nest, but absent-mindedly swallowing the fly herself, would go off. We had a wonderful chance to study the coloring of this rare bird. The cock-bird had a bright black eye which showed vividly against his yellow cheek, as did his long black bill. His colors were gray, yellow, and olive. The underside of his tail was pure white, and he had a white edge to his wings, while the top of the wings was greenish-yellow. The whole head, throat, and breast were of an intense golden, almost orange yellow, and the wings were bluish-gray. The bird itself was just about the size of the common black-and-white warbler. The female was of the same coloring, only much paler.