The movements of this Woodpecker are interesting, for, like its sister species, it moves with equal facility either upwards or downwards, sidewise or backwards upon a tree trunk. From time to time it will stop and seem to listen, and, finally bracing itself with the stiff feathers of its spiney tail, it will deliver powerful blows with its chisel-like bill at some point that will be likely to furnish a dainty morsel of food. There is little doubt that its sense of hearing is very acute and that it can detect the slightest movement of an insect in the bark or wood of a tree that to other animals would be imperceptible. The flight of the Hairy Woodpecker is like that of the other species of its group. It is wavering and undulating, seldom protracted and usually consisting of a number of short vibrations of the wings. When alighting, they grasp the object with both feet simultaneously. This Woodpecker is the earliest of all the family to build its nest. Mating begins in the latter part of March, and at this time the birds are exceedingly noisy. The male when not feeding will resort to some dead limb and vigorously drum and “the louder the noise produced, the more satisfactory it appears to be to the performer.” Regarding the building of the nest, Major Bendire says: “Both sexes take part in the labor, and it is really wonderful how neat and smooth an excavation these birds can make with their chisel-shaped bills in a comparatively short time. The entrance hole is round, as if made with an auger, about two inches in diameter, and just large enough to admit the body of the bird; the edges are nicely beveled, the inside is equally smooth, and the cavity is gradually enlarged toward the bottom. The entrance hole, which is not unfrequently placed under a limb for protection from the weather, generally runs in straight through the solid wood for about three inches, and then downward from ten to eighteen inches, and some of the finer chips are allowed to remain on the bottom of the cavity, in which the eggs are deposited. Both dead and living trees are selected for nesting sites, generally the former. When living trees are chosen, the inner core, or heart of the tree, is usually more or less decayed. These nesting sites are nearly always selected with such good judgment that such obstacles as hard knots are rarely encountered; should this occur, the site is abandoned and a fresh one selected.” The male, after the work is completed, will often excavate one or more holes in the same tree in order that he may have a resting place at night near to his mate. A VARICOLORED FROG.