OONE of the difficulties of the scientific ornithologist is to differentiate species. This bird is often confounded with the Flycatchers, and for a very good reason, its habits being similar to those of that family. It is almost a counterpart of the Kingbird, (See Birds, vol. ii, p. 157) possessing a harsher voice, a stronger flight, and, if possible, a more combative, pugnacious spirit. It is a summer resident, is common in the western United States, and occasionally a straggler far eastward, migrating southward in winter to Guatemala.

Col. Goss, in his history of the birds of Kansas, one of the most comprehensive and valuable books ever published on ornithology, says that the nesting places and eggs of this species are essentially the same as those of the Kingbird. They are brave and audacious in their attacks upon the birds of prey and others intruding upon their nesting grounds. Their combative spirit, however, does not continue beyond the breeding season. They arrive about the first of May, begin laying about the middle of that month, and return south in September. The female is smaller than the male and her plumage is much plainer.

Mr. Keyser "In Birdland" tells an interesting story which illustrates one of the well known characteristics of the Kingbird. "One day in spring," he says, "I was witness to a curious incident. A Red-headed Woodpecker had been flying several times in and out of a hole in a tree where he (or she) had a nest. At length, when he remained within the cavity for some minutes, I stepped to the tree and rapped on the trunk with my cane. The bird bolted like a small cannon ball from the orifice, wheeled around the tree with a swiftness that the eye could scarcely follow, and then dashed up the lane to an orchard a short distance away. But he had only leaped out of the frying-pan into the fire. In the orchard he had unconsciously got too near a Kingbird's nest. The Kingbird swooped toward him and alighted on his back. The next moment the two birds, the Kingbird on the Woodpecker's back, went racing across the meadow like a streak of zigzag lightning, making a clatter that frightened every echo from its hiding place. That gamy Flycatcher actually clung to the Woodpecker's back until he reached the other end of the meadow. I cannot be sure, but he seemed to be holding to the Woodpecker's dorsal feathers with his bill. Then, bantam fellow that he was, he dashed back to the orchard with a loud chippering of exultation. 'Ah, ha!' he flung across to the blushing Woodpecker, 'stay away the next time, if you don't fancy being converted into a beast of burden?'"

Eggs three to six, usually four, white to creamy white, thinly spotted with purple to dark reddish brown, varying greatly in size.