me, but would not come out until they were sure that the hawk was gone, as evidenced by the awakening activities of the other kinds of birds. I then gave them both food and, following what now seems to be established precedent, as soon as they had finished, they went back to the nest 60 yards away and resumed their building operations. Shaping nest. They have begun shaping the nest now with their bodies. They worked quite energetically during the half hour I watched them, then I left. Returning after another half hour, they were still at it, but the female came down at once without being enticed by me in any way and approached me for food, then back to work again. A few minutes after this, I was out in the open and she came for more food, running from bush to bush, keeping an eye open for hawks, returning to work again after eating. February 23rd. Materials used. At 9 A.M. the birds were not working, but soon appeared and both began carrying material to the nest, both doing about the same amount of work. They are now using much smaller twigs; mostly oak which they find conveniently at hand under the old oak; some, however, they break off of the sage brush. They are also now carrying up loose fibre from the soap-root bulbs. I cut up some rope yarn to see if I could interest them, but they were very busy and paid no attention to me or my offerings. Test with rope yarn. About 11 o'clock work slackened and they began to show more inter- est in their surroundings. In the presence of Mr. Sampson I offered the female some rope yarn, but she inspected it only as a possible source of food. I then held a meal-worm with the yarn, and, in getting the worm, the yarn went with it and she ran off evidently in surprise, but dropped the yarn when she swallowed the worm, showing no further interest in it, although she wanted nesting material at the time as proved by her going immediately to a sage to break off fine twigs.