.--On July 13, 1958, four Rufous Hummingbirds, Selasphorus rufus, were observed feeding on the sap of the English walnut, ]uglans regia L. The sap was exuding from holes made by the feeding activity of the Yellow-bellied (Red- naped) Sapsucker, Sphyrapicus varius nuchalis. This activity was observed in a clearing at the site of an abandoned sawmill, approximately two miles northeast of Golden and Silver Falls State Park, in the Coast Range mountains of western Oregon. A single English walnut was located at the edge of an old apple orchard, about 150 feet from a small mountain stream. When first observed, the sapsucker was feeding in the upper branches of the walnut. The trunk and main branches were practically girdled by the hundreds of holes which had been made by this species. Two pairs of Rufous Hummingbirds were flying around the tree. Occasionally they darted down to within six inches of the sapsucker but made no attempt to molest the larger bird. As I approached the walnut the sapsucker became alarmed and flew to a nearby apple tree. Immediately one of the hummingbirds flew to the spot vacated by the sapsucker and hovered over the limb, while inserting its long bill into one of the newly-made holes. Only once during the 20 minute period of observation did two birds feed in adjacent holes at the same time. Occasionally the birds would perch while feeding. They continued feeding even when I climbed the tree and approached to within two feet of them. On visiting the same spot two hours later two of the hummingbirds were observed in the vicinity of the walnut but were not feeding. At this time a sapsucker was feeding in an adjacent apple tree. At no time were hummingbirds observed feeding on the sap of tree species other than the walnut. The sap of trees is not commonly thought of as food for hummingbirds, and there is only occasional mention of this type of feeding activity in the literature. Barrows (Michigan Bird Life, p. 387. 1912. Mich. Agric. COIL) mentions the occasional use of the sap flowing naturally from trees as food by the Ruby-throated Hummingbird, Archilochus colubris. Obviously hummingbirds can only utilize trees from which the sap is already flowing. Such food sources are rather rare. Bolle (cited in Bent, U.S. Natl. Mus. Bull., 176, p. 343. 1940) noted the Ruby- throated Hummingbird feeding at holes made by the Yellow-bellied Sapsucker. Grinnell and Storer (1924. Animal Life in the Yosemite, p. 354. Univ. Calif. Press) reported Anna's Hummingbird, 1/2alypte anna, feeding on the sap of the 'golden oak' at the holes of the Yellow-bellied (Red-breasted) Sapsucker, Sphyrapicus v. ruber. Woodbury (Condor 40(3): 125. 1938) observed the Rufous Hummingbird feeding from workings on willow trees of the sapsucker, S. v. nuchalis. Woodbury did not mention whether other food sources were generally available in the vicinity. In the present instance there were ver few flowers present in the small clearing where the birds were observed, and none in the surrounding virgin Douglas Fir forest.--R. WEGrRT, Dept. of Zoolog'y, University of Michigan, Ann Arbor, Michigan.