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 Jan., 1915 THE NESTING OF THE BLACK SWIFT 11 Graflex for a snap at the flushing bird. Anticipating some speed I did not trust myself to release the shutter after recognizing the bird on the mirror, but held on the water and watched the nest instead. It was well I did so, for when V. let down his "devil-box" abreast of the bird, [ pressed the button upon the instant of her emergence. Even so I caught her, a mere black smear on the plate, over the water and some forty feet away from the nest. Again our bene- factress winged straight to sea and passed from sight. It was a Black Swift, no doubt of that; but it took the sight of other birds hurtling about another sea-cliff in amorous (and as yel unfruitful) pursuit, to confirm the impression of reality. After "snapping" the egg in situ with the Graflex, I packed it away se- curely and lifted the nesting cornice, earth, grass, rootlets and all, clear of its limestone moorings. Fig. 7. EGG (NO. 11) OF BLACK SWIFT, in situ The egg, figured herewith in comparison with that of the White-throated species, is seen to be about three times larger. This, in view of the fact that the birds themselves are approximately the same size, is a sufficient comment- ary on its singular number. The bird could not take care of many such. The nestling, too, must be much further advanced at the time of hatching than in the case of those species which raise four or five at once. But it is passing strange that this aberrant Swift should ape the sea-birds. notably the Murres, in this respect of having a single large egg. But although this bird has been caught thus "dead to rights" posing as a sea-bird, I do not for a moment believe that sea-cliffs constitute its habitual nesting site. The Black Swift is properly a bird of the high mountains, and it will be found nesting in the crevices of lofty mountain walls. To cite only re-