359 Gilmore SLIMNER SLIMNER BILLED SHEARWATERS TO 1931 areas off Priest's Rock & adjacent jutting headlands. Oct. 7 Akutan Pass, W. Aleutian Is. While crossing the rough waters of the east side of the pass we ran through several thousand of these birds. The flock extended in a long line of a general north and south direction and just the north on the horizon we could see myriads of these swift flyers, seeming like notes in a sunbeam. The water was rough from rip tide and N.W. wind and none of the birds were resting on the surface but were steadily skimming the surface of the water whether in deep trough or on wave crest. One can watch these birds, for each individual acts by himself and affect is a mass of wheeling, darting, gliding birds. Their actions are cyclic: they fly on rapid pirouettes to a height of about 20 ft & then glide swiftly down over the waves, following each trough & crest with amazing precision.