but this produced very little sound, and he soon gave it up and flew away.
After about ten minutes both male and female birds appeared, and danced about on the trunk and the branches of the tree close to the hole, their antics being most amusing to watch. Presently the female bird perched upon a horizontal branch slightly below the level of my line of vision, and I actually observed the male bird tread her for some seconds. During this operation the male bird balanced himself by keeping both wings fully extended, and I obtained a particularly fine view of the outline of the wings and their beautiful markings. Fortunately my ambush proved an excellent one, and my presence was entirely unsuspected, although I was so close to the birds that I hardly had occasion to use my glasses. I was particularly impressed by the fact that both birds constantly uttered the peculiar soft twittering notes I had previously described—a kind of whispered sound of pleasure and satisfaction, as it were, to one another, which was most pleasing to the ear; while they never once gave utterance to their somewhat harsh, laughing, almost Owl-like cry.
Two days later I took up my position again at 7 a.m., and, after watching nearly half an hour, was amply rewarded, as both birds at length appeared. The male went inside the hole, and disappeared from view; but presently his head appeared, and a beakful of chips of wood was thrown from the nest and scattered on the ground. He worked away busily, and it was interesting to observe the curious jerk he gave to his head as he disposed of each beakful.
Sometimes one and sometimes both birds were on the tree, but the female appeared to do no work. When alone she perched perpendicularly on the tree-trunk, and peered into the hole; then she went inside and peered out; the next minute she was out again, and was apparently testing the hole by going in and out repeatedly, making a careful inspection of her future home both inside and out. On the two following days I again watched the male bird tapping on his pine-wood sounding-board, and was struck by the fact that the interval between each series of taps was longer than when I had first observed it earlier in the month. Another curious thing was that a final tap was added separately, as though one had been forgotten. After this the tapping was
