I have already mentioned the housekeeping of a couple of chickadees in a low birch stump. Theirs was one of three titmouse nests just then claiming my attention. I visited it frequently, from the time when the pair were hard at work making the cavity up to the time when the brood were nearly ready to shift for themselves. Both birds took their share of the digging, and on several occasions I saw one feeding the other. After the eggs were deposited, the mother (or the sitter) displayed admirable courage, refusing again and again to quit her post when I peered in upon her, and even when with my cane I rapped smartly upon the stump. If I put my fingers into the hole, however, she followed them out in hot haste. Even when most seriously disturbed by my attentions the pair made use of no other notes than the common _chickadee, dee_, but these they sometimes delivered in an unnaturally sharp, fault-finding tone. My two other titmouse nests were both in apple-trees, and one of them was in my own door-yard, though beyond convenient reach without the help of a ladder. The owners of this last were interesting for a very decided change in their behavior after the young were hatched, and especially as the time for the little ones' exodus drew near. At first, notwithstanding their door opened right upon the street, as it were, within a rod or two of passing horse-cars, the father and mother went in and out without the least apparent concern as to who might be watching them; but when they came to be feeding their hungry offspring, it was almost laughable to witness the little craftinesses to which they resorted. They would perch on one of the outer branches, call _chickadee, dee_, fly a little nearer, then likely enough go further off, till finally, after a variety of such "false motions," into the hole they would duck, as if nobody for the world must be allowed to know where they had gone. It was really wonderful how expert they grew at entering quickly. I pondered a good deal over their continual calling on such occasions. It seemed foolish and inconsistent; half the time I should have failed to notice their approach, had they only kept still. Toward the end, however, when the chicks inside the trunk could be heard articulating _chickadee, dee_ with perfect distinctness, it occurred to me that possibly all this persistent repetition of the phrase by the old birds had been only or mainly in the way of tuition. At all events, the youngsters had this part of the chickadese vocabulary right at their tongues' end, as we say, before making their _début_ in the great world.