+Sarcidiornis regia+, _Burm. La-Plata Reise_, ii. p. 513 (Tucuman); _id. P. Z. S._ 1872, p. 365. +Sarcidiornis carunculata+, _Scl. et Salv. P. Z. S._ 1876, p. 377; _Sclater, P. Z. S._ 1876, p. 695, pl. lxviii.
_Description._--Head and neck white, spotted with black, hind neck almost black; base of neck and body beneath white; flanks black; back and wings black; secondaries glossed with bronze, the scapulars with purple; lower back grey; tail brown; bill, with caruncle on the culmen, and feet black: whole length 30·0 inches, wing 15·0, tail 6·0. _Female_ similar, but rather smaller.
_Hab._ Brazil, Paraguay, and northern confines of Argentina.
Dr. Burmeister met with this Duck in the province of Tucuman, and it probably occurs also in other places on the northern frontiers of the Republic.
+Cairina moschata+, _Burm. La-Plata Reise_, ii. p. 514 (Paraná, Santa Fé, Tucuman); _id. P. Z. S._ 1872, p. 367; _Scl. et Salv. Nomencl._ p. 120; _iid. P. Z. S._ 1876, p. 378; _White, P. Z. S._ 1882, p. 625 (Salta).
_Description._--Whole head and neck and body beneath brownish black; belly closely banded with narrow white lines; back greenish purple, with the feathers edged with black; scapulars and elongated tertials and tail bright shining green; secondaries edged with metallic blue; primaries black; upper and under wing-coverts and axillary plumes white; flanks slightly tinged with green; bill with caruncles red; feet black: whole length 29·0 inches, wing 15·0, tail 7·5. _Female_ similar, but smaller.
Everyone is familiar with this species in its domestic state, called in the Argentine country _Pato creollo_ (Creole Duck); but the wild bird, called _Pato real_, is little known, although a few stragglers are seen as far south as Buenos Ayres, where I have met with eight or nine examples. Concerning the distribution and habits of this species Messrs. Sclater and Salvin write:--"The Muscovy Duck, so well known in a domestic state nearly all over the world, is a native of the hottest portion of tropical America. It is usually found in lowland swampy districts; and where there are extensive forests it not unfrequently abounds. During the day the birds remain in the forest-swamps; but towards evening numbers may be seen sitting on the lower boughs of trees standing on the margin of a clearing.