Dance of Ypecaha Bails.
voice, exerted to its utmost pitch and expressive of extreme terror, frenzy, and despair. A long, piercing shriek, astonishing for its vehemence and power, is succeeded by a lower note, as if in the first the creature had well nigh exhausted itself: this double scream is repeated several times, and followed by other sounds, resembling, as they rise and fall, half smothered cries of pains and moans of anguish. Suddenly the unearthly shrieks are
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The Naturalist in La Plata.
renewed in all their power. While screaming the birds rush from side to side, as if possessed with madness, the wings spread and vibrating, the long-beak wide open and raised vertically. This exhibition lasts three or four minntes, after which the assembly peacefully breaks up.
The singular wattled, wing-spurred, and long-, toed jacana has a remarkable performance, which seems specially designed to bring out the concealed
Wing-display of Jacanas.
beauty of the silky, greenish-golden wing-quills-The birds go singly or in pairs, and a dozen or fifteen individuals may be found in a marshy place feeding within sight of each other. Occasionally, in response to a note of invitation, they all in a moment leave off feeding and. fly to one spot, and, forming a close cluster, and emitting short, excited, rapidly repeated notes, display their wings, like beautiful flags grouped loosely together: some hold