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 84 TIIE CONDOR Vol. XIX ings on the dark feathers were very much in accord with the general black and white color scheme of tile gravel bar upon wbieb tile bird bad squatted, endeavor- ing to escape notice by remaining motionless. The change from natal down to the imlnature plumage is well illustrated in this individual. Tile yotmg sandpipers were found feeding in the shallower pools, where the water was less than one ineb deep. At times as many as five were noted in an area one yard square. They congregated along the water's edge, picking up, as the tide slowly receded, many bits of food. The nature of this provender I could not make out although the yonng birds would often come within twenty feet of me when I remained motionless for a few minutes. Tile old birds were mneh more shy, often taking flight or retreating to distant gravel bars upon my ap- proach. Considerable time was spen by both yonng and old in making short flights about the barbor. These flights alternated with periods of food getting, and were seemingly in preparation for tile fall migration. It was only a few days then until the bulk of tile species left on their southward journey. Fig. 31. IMMAi'URE BAIRD SANDPIPEIi HIDING ON GRAVEL ILAR. HERSCHEL ISLAND, YUKON, JULY 30; 1914. Murdoek reports the last bird seen at Point Barrow on August 12. In 191.3 we noted the last of the species on August 11, near Barter Island, Arctic Alaska; in 1914 I saw none after August 15. There is no apparent reason for the sand- pipers leaving their summer home as early as they do, as the weather is very much more genial at this time than it is during the breeding season, and the food supply is certainly as abundant. The main body of Baird Sandpipers return south by the spring migration route, between the Mississippi and the Rockies, but there is a tendency to spread out along both the Atlantic and Pacific sea coasts. Swarth (Univ. Calif. Publ. Zool., v, 1910, p. 51) noted the first fall migrant at Thomas Bay, in southeastern Alaska on August 15, 1909, and the birds were common a week later. The spe- cies bas been considered rare on the Atlantic coast in fall, but recent observations have produced numerous records until it seems now that the bird must be more common there than it was believed to be. The birds reach their winter home in southern South America in September. Museum of Vertebrate Zoology, UMversity of CaliforMa, March lt, 1917.