1687. thus showing , probably, that the nesting impulse has not subsided for the season as yet. (Tests were made last year which showed that, when I climbed to one of his nests while the breeding urge was still strong, he would, on seeing me there, come and settle in his nest; whereas out of season, he would pay no attention to my action even when I pretended to destroy his nest. Nesting of the Allen humming- bird. On the 7th., I began to observe more closely the activities of a female Allen's humming-bird which had, on the first of June, been observed fluttering about the end of a droop- ing branch of a live oak close to a window of the stair landing. During the next few days this bird was seen to carry nesting material and place it at this place, working principally during the early forenoon, but in casual fashion, sometimes not visiting the spot for hours. Although the beginnings of a nest could be seen the first day on the seventh, when I arranged to take colored motion pictures with a 4½ inch telephoto lens, from the landing and 9 feet from the bird, and slightly higher than the nest. The nest, by the way, is 16 feet above the ground--an unusual height, I believe, for this bird. It was found that direct sunlight shone on the nest between 3:25 P.M. and 4 P.M.; at other times it was either in the total shade of the house or in the partial shadow of the tree itself. A single leaf, to the stem of which the nest was attached at one point, obstructed full view of the nest from the landing, so an arrangement was rigged up consisting of pruning shears lashed to the end of a bamboo pole, and a cord running through eyelets by which the shears could be operated. This was used to clip off the leaf-- a rather delicate operation, at 7 feet distance, without injuring the nest. When the bird had left for (presumably) more nesting material the apparatus was put into operation; but the bird returned in the middle of it, buzzed in my face first, then went to the nest and sat in it and worked on it while the shears must have been in actual contact with the nest! Compare Dawson's statement (Birds of California) in reference to the Allen hummer: ".....of our seven species, Allen's is consistently the most retiring and secretive, as well as the wildest when found". The bird left before the job was finished, but returned immediately afterward and resumed work. A series of motion pictures was taken, using various sized stops, in order to determine which aperture best fits the lighting condi- tions at the nest, as it is hoped that it may be possible to obtain a sequence covering the entire cycle from construction to the leav- ing of the young. The house-wren (and other "predators") may, how- ever, rule otherwise. It was possible to observe the building operation from a distance of about six feet, and it was at once seen that--at the present stage of construction, when the nest has but a slight de- pression representing the future bowl--the bird shapes the outside by sitting inside and reaching out and under the nest with her bill and pressing the latter against the outer wall while drawing the bill upward. Further, to my astonishment, it was seen that, during this action, the tongue was fully extended and was used in a man- er which suggested irresistibly that the bird was applying saliva, or perhaps some adhesive secretion to the exterior as a binder or cementing material. She also rubbed her cheeks (as a brush) around and a little below the periphery, heightening the suggestion. Still later, on returning and carrying nothing visible to the eye, she