Major Bendire (1895) mentions a nest, found by Dr. A. K. Fisher in Garden Canyon in the Huachuca Mountains, on May 14, that was “in a large maple which overhung a stream. The cavity was situated in a dry branch, about 20 feet from the ground, and was about a foot in depth. It contained four young, which were still naked.” There are two sets of four eggs each in the Thayer collection; one was taken by O. W. Howard in the Huachuca Mountains on April 24, 1902, from a nest in a mescal stalk, 8 feet from the ground; the other was collected by Virgil W. Owen in the Chiricahua Mountains, on April 22, 1906; the entrance to the cavity was 9 feet up on the under side of a slightly leaning, dead and decaying stub of an oak limb in a dead tree. _Eggs._--The Arizona woodpecker apparently lays either three or four eggs; we have no record of more or fewer. The few that I have seen are practically ovate; they are pure white and some are quite glossy, others less so. The measurements of 27 eggs average 22.82 by 17.33 millimeters; the eggs showing the four extremes measure =24.0= by =18.0=, =19.9= by 16.7, and 22.5 by =16.5= millimeters. _Young._--The period of incubation does not seem to have been definitely determined, but it is probably about 14 days, as with other _Dryobates_. Both sexes assist in this task, and probably in the care of the young. H. S. Swarth (1904) writes: About the third week in April they commence laying their eggs, and after the middle of June the young birds begin to leave the nest, and soon become quite abundant. I have never had any difficulty in approaching these birds as they are usually quite tame and unsuspicious; far more so than the generality of woodpeckers, and the young birds are noticeably so. I have several times stood within ten feet of a young bird, easily distinguishable by his red cap, as he was industriously pounding on a limb without seeming in the least disturbed by my presence, or showing any inclination to leave. On one occasion the confiding, and in this case inquiring nature of the bird occasioned rather a laughable scene. An acquaintance in the mountains, passing the camp one day stopped to lead his horse down to the well which supplied us with water. A young Arizona Woodpecker was sitting in an oak tree close by, and soon after the horse began drinking he flew down, and lighting on the animal’s hind leg as on the side of a tree, hit it a vigorous rap or two. The horse and its owner appeared equally surprised, and both moving a little the bird retreated to his tree. It wasn’t a minute before he was back again, this time on a front leg, where he went to work with such energy as to start the horse plunging and kicking in an effort to get rid of its curious assailant. The woodpecker left but did not seem to be particularly frightened, as he sat on the wooden curb of the well until