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Show 1891.] BIRDS O F T H E P H O S N I X ISLANDS. 291 numbers. They were built of small dead twigs of the plants of the island, placed a foot or so above the ground on the spreading branches of the Sida and on the beaten-down tussocks of grass. The nests were placed as near together as supports could be found, and there were well-defined limits to the colonies, although the bushes beyond these limits appeared to be just as well suited for the purpose as those within. Each nest was occupied by a bird. As one approached some of these took flight and joined the wheeling crowd overhead, but the rest remained sitting and allowed themselves to be touched with the muzzle of my gun, only chattering their bills by way of remonstrance. Both males and females were to be seen engaged in the duties of incubation. The following table gives the points of difference which I noted between the sexes : - Males. Females. Scarlet throat-pouch present. No throat-pouch. Long nape- and back-plumes. No long nape-plumes. Bill varies in colour from black to Bill varies in colour from piuk to greyx. grey. Feet and skin round the eye black. Feet and skin round the eye red. Wing-coverts black. Wing-coverts pale brown. Breast and belly dark except for a Breast and fore part of belly white ; white streak on each side of the nape-band white to tawny. latter. No pale nape-band. A few of the birds had tbe white or pale tawny heads of the immature plumage. They were in the proportion of about 1 to 100 of those in ordinary plumage. I saw none of these on the nests. The throat-pouch of the male is a most striking object. When fully distended it reaches forward as far as the end of the bill and downwards so as to completely hide the breast-a great smooth semitransparent balloon of the most brilliant scarlet, which contrasts finely with the dark metallic tints of the plumage. If any of the birds in a group had their pouches distended, there were generally several in this condition, as though they were vieing with one another in the exhibition of their attractions. From several parts of the group came a low vibrating note, a combination of a whistle and a purr accompanied by the sound of the chattering of their bills. While uttering this note the bird leans back on the nest, with the head thrown right back, the pouch fully extended, and the wings half spread and shaken with a quivering movement. The female birds meanwhile were either wheeling overhead or sitting on the edge of the nest near their admirers. The pouch is not rapidly filled or emptied. When a bird with a half-distended pouch takes flight, the latter is carried from side to side with the movement through the air, gradually diminishing in size. In the undistended state the bare wrinkled skin is completely 1 When the bills are grey, the colour is due to the rough surface aud appears to be a sign of age. |