Note: Information is dated. Do not rely on it.Passenger Pigeon. The American wild pigeon, Ectopistes migratorius, at one time very abundant in the Mississippi valley and in the states eastward, but now very scarce or possibly extinct. In the early days of the United States these pigeons were so numerous that at times the flocks covered the entire visible heavens for hours at a time. As late as 1860 they were still so plentiful that, when migrating in the spring or autumn, flocks were visible almost constantly at all hours of the day. When roosting at night their weight broke down large branches and even small trees; advantage was taken of this gregarious habit to kill them, when sleeping, in great numbers. In 1911 they were so nearly extinct that the American Ornithologists' Union made an organized effort to discover and save the remnant then living, and rewards aggregating over $2000 were offered for the discovery of undisturbed nestlings. The passenger pigeon is 16 inches long, with a ruddy breast, blue-gray back, and a pointed tail. Its nest is always built of twigs in shrubs or trees, and contains one or two white eggs one and a half inches long. The mourning dove, which might be mistaken for the wild pigeon, is 12 inches long, brownish on the back, and has a black spot on each side of the neck. It nests on or near the ground, frequently using a brush-heap or low-hanging branch as the support. The nest usually contains two white roundish eggs each an inch long.