The Spoonbills and Ibises constitute a homogeneous family of Herodiones, which have a wide distribution over the earth's surface, although mostly prevalent within intertropical limits. They fall naturally into two groups--the Ibises, distinguished by their elongated, compressed, and sickle-shaped bills; and the Spoonbills, at once known by the peculiar form of the same organ, which is much expanded at its termination. Of about twenty-five known species of Ibises, the Neotropical Region possesses eight or nine, and of these four occur in Argentina. Of the Spoonbills only one is Neotropical, and that is met with throughout the southern portion of South America. 327. PLEGADIS GUARAUNA (Linn.). (WHITE-FACED IBIS.) +Plegadis guarauna+, _Baird, Brew., et Ridgw. Water-B. N. A._ i. p. 97. +Falcinellus guarauna+, _Elliot, P. Z. S._ 1877, p. 505. +Ibis falcinellus+, _Hudson, P. Z. S._ 1870, p. 799 (Buenos Ayres). +Falcinellus igneus+, _Durnford, Ibis_, 1877, p. 189 (Buenos Ayres). +Plegadis falcinellus+, _Gibson, Ibis_, 1880, p. 155 (Buenos Ayres); _Barrows, Auk_, 1884, p. 272 (Entrerios). +Ibis chalcoptera+, _Burm. La-Plata Reise_, ii. p. 511 (Paraná, Mendoza). _Description._--Head, neck, and under surface purplish chestnut, with a white band round the base of the bill; back with metallic reflexions; wings and tail bright green, with bronzy reflexions; band across upper wing-coverts chestnut; bill reddish grey; feet brown: whole length 22·0 inches, wing 9·0, tail 3·0. _Female_ similar. _Hab._ Central and South America. This form of the well-known "Glossy Ibis" of Europe is one of our most abundant waterfowl on the pampas, and appears in spring in flocks; but as their movements are somewhat irregular and many individuals remain with us through the winter, their migrations probably do not extend very far. In summer they are found beside every marsh and watercourse, briskly wading about in the shallow water and plunging their long curved beaks downwards at every step. When taking wing they invariably utter a loud _ha ha ha_, resembling hearty human laughter, but somewhat nasal in sound. They frequently leave the marshy places and are seen scattered about the grassy plains, feeding like land-birds; and on the pampas they often congregate about the carcass of a dead horse or cow, to feed on the larvæ of the flesh-fly in company with the Milvago and the Hooded Gull.