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Jan., 1915 BIRDS OBSERVED ON FORRESTER ISLAND, ALASKA 39 white in color with a faint ring of red spots about the larger end, though this last named character is not invariable. The exact period of incubation was not determined, though it is appar- ently about two weeks. As pre?'iously mentioned the first eggs were laid about June 30, and chicks fully five days old were found on the 19th of July. The duty of incubation rests on either parent as both males and females were found during the day. The prevalence of storms and rough weather made it neces- sary to confine our observations to the day-light hours so that no first-hand information can be given regarding the return of the absent mate and the feeding of the young, but the natives are agreed that the birds change places on the nest after nightfall, and after an interval of about four hours the day's shift takes place. The flight of the parent birds upon leaving home is always to the westward. In other words they do not occur in the neighborhood of the mainland or the islands along the coast, but hunt their food on the high seas far from any body of land. An examination of the stomach contents of three individuals showed that they had been feeding upon some species of crustecean, apparently a shrimp, though this food product had been reduced to a pulp and so greatly digested that a few particles of chitin were-alone recognizable. The resulting semi- fluid, highly oily substance, having the characteristic musky odor of the bird and burrow, is vomited out when the bird is disturbed, apparently for pur- poses of defense. It is difficult to estimate the number of these birds nesting on South Island. The indians sometimes call the place "the basket" since it is so full of holes, but when asked regarding the number of holes or birds their guesses ranged from ten thousand to two hundred and fifty thousand. In a rough way the island was measured into a number of plots and in each of these the num- ber of nests was estimated. The result totalled not far from seventh-five thousand, or one hundred and fifty thousand birds, and this is certainly a conservative estimate. 10. Oceanodroma furcata. Forked-tailed Petrel. The Fork-tailed Petrel is likewise confined to South Island, where it nests in small numbers when compared with the Leach Petrel. Following the directions of Captain John their nests were found on the summit of the heights adjacent to the cen- tral ravine, but Qwing to the fact that their burrows are in no manner differ- ent from those of the Leach Petrel, among which they are placed, and that fully twenty-five of these last named birds must be dug out in 'order to find one forked-tailed, no extended search was made for this species. Two dead individuals were picked up at the entrance of uncompleted burrows, but there is no practicable method whereby the limits of the colony can be accurately defined. The density of the growth of spruce on the summit results in fairly clear ground, and great numbers of burrows occur in the soft soil in the open places or under logs or about the roots of trees. As indicated above there is no token whereby one can distinguish the homes of the forked-tailed (though one nest w?s located by one of the characteristic light colored feathers in front of the entrance) and it is accordingly impossible to accurately estimate the popula- tion of the colony. It is safe to conclude with the natives that the species is confined to high ground, and that not more than one burrow out of twenty-five