102 THE CONDOR Vol. XIII point where I resided in the Dakota country, the crescendo chant of the Oven- bird (Seiz?rz?s az?rocafbz'lf?is) was heard in spring and summer, and on two occasions I found the nest of this species. When the night falls, and near the water the frogs sing and croak; when the slight breezes cause the pines to sigh; when, like ghouls, the coyotes yelp and wail amid the moon-kissed hills, whereon, exposed to sunshine and to rain, rest the rude coffins of the Sioux--then the sound that, above all others, arrests the atten- tion, is the succession of curious utterances of the Long-tailed Chats (ircteria vire?zs fon?icaz?cla) in the undergrowth along the creek. Day and night for a consider- able period after the middle of May, I could hear them, and when I first witnessed the actions of the male as he mounted high in the air, and then descended in a series of short, jerky flights, I realized the appropriateness of one of his common names--clown. And no mountebank ever was more gaily attired than he. Red-headed Woodpeckers, while not remarkably abundant, were [common enough among the trees near the water-courses from May 20 to the middle of Sep- tember, and ever and anon, one or two could be seen working away at a post, or sitting on the ridge-board of a building. Or again, especially in the autumn, the young and old spent much time together engaged in flycatching. This, by the way, has become a very common trait of these birds. While I do not venture to prophesy, yet it may be said that from such small beginnings as this occasional re.creation, marked changes in habit or structure often take their rise. Just at present it would be hard to believe that these birds might sometime be driven by natural selection to take regularly to this method of obtaining insect food. Still, should timber become exceedingly scarce, such a result might follow. Moreover I believe that at the present day, even, use and habit may be effecting slight .changes in the Red-head's ways'of life. The habit of flycatching, which is in- dulged in by all the species of Melanerpes, the genus to which this bird belongs, is no doubt inherited; and it would be strange indeed if continued use of the muscles called upon did not strengthen and modify them, as well as enable the bird to at- iain skill in their exercise; and these acquirements would be transmitted to the progeny. Then, should the kinds of trees beco?ne scarce wherefrom the wood- peckers are wont to search out their food, it is possible to believe that natural se- lection would preserve those birds that were best enabled to make a living by fol- lowing the Kingbird's trade, and that in a few thousand generations it would be difficult indeed for the shade of Audubon, on beholding the modified descendant of Melanerpes, to tell what manner of bird was before him! It is more than probable' that the genus to which the comnfon Flicker belongs was in remote times nearer than now to the typical woodpeckers, which lead a strictly arboreal life; and glancing from them to him we see the changes that have been wrought. Natural selection has operated upon tlie coloration o? the Flicker's
upper parts and rendered them protective to the owner in that they make him in-
conspicuous as he "hunts bugs" upon the ground, and directlye to his companions as he rises therefrom in flight. Moreover, the same agency, assisted by use and wont, has effected other modifications. And why, in the light of these facts, should it be impossible to accept the view that the Red-head, also, may one day become altered in form and habit? But all such changes ultimately depend upon modifications m the environment; unless these occur the organism remains un- altered. I think it was when severe storms swept over the plains, driving the birds to the vicinity of the buildings and haystacks that I felt for and with them most.
