AT Pearson Tyrannus panthalodon Uraybarco, 55 mi. E.N.E. y Aneqipa 15,300 ft. March 27 1952 Dept. y Pain Sat at nest # 2 from about 2 - 5 P.M. A bird had returned to the nest at 12:35 (see O.P.P.) and was still sitting at 2 P.M. Over the nest how the bird frenet for a couple minutes, but spent a good deal of time reaching out of the nest to peck at something, frequently drawing an object in toward the nest and tucking it in. A few minutes before 3 P.M. the bird got off the nest and took a few steps South, which was also up-wind from the nest. There was a little low grass growing about a foot south of the nest which the bird pecked at. It would take a piece in its bill and throw it over either right or left shoulder. The bird did this about 100 times, also throwing both green and dried Pycnophyllus, which was about a yard west of the nest. Then the bird turned north + disappeared over the nest ridge. Inspected the nest - still 8 eggs - and most of the eggs were covered with the driest bits of grass. Bird came up the gulley below the nest at 4:25. Climbed onto nest (didn't see what happened to grass), head facing south. Restless, pecking at nest, stood on egg for a bit before it sat down. Gradually turned around until it faced north again. Interrupted by sirdine + dog. OPP took over at 5 P.M.