This bird in general habits has several points of resemblance with the _Furnarius cunicularius_, but differs in some other respects. Its flight is somewhat similar, but it shows two red bands on its wings, instead of one, by which it can be distinguished at a distance: instead of walking it only hops; it feeds entirely on the ground, and in its stomach I found scarcely anything but Coleopterous insects, and of these many were fungi feeders. It often frequents the borders of lakes, where the water has thrown up leaves and other refuse. It likewise may be met with in all parts of the open grassy plains of Banda Oriental, where (like the _Uppucerthia_ at the Rio Negro) it often turns over dry dung. Its note is very like that of the _F. cunicularius_, but more acute, and consists of a shrill cry, quickly reiterated so as to make a running sound. I was informed that, like that bird, it builds its nest at the bottom of a deep burrow. This species is common in La Plata, the Falkland Islands, and Tierra del Fuego; in the latter it frequents the higher parts of the mountains, or those exposed to the western gales, which are free from forests, for it is a bird that exclusively lives in open countries and on the ground. I believe it is not found in Chile; nor is it common on the coast of Patagonia. This species in its habits is very different from the three following closely allied ones, since the latter never, or most rarely, leave the sea beach, whilst this bird, excepting by chance, is never seen there, but always in the interior country. Nevertheless with this marked difference in habits, (there are several other points beside that of the station frequented), if the preserved skins of _O. parvulus_ and _O. vulgaris_ were placed in the hands of any one, even perhaps of a practised ornithologist, he would at first hesitate to consider them distinct, although upon closer examination he would find many points of difference,—of which the much greater strength of the feet and the greater length of the tarsus are conspicuous in those species, which live amongst the stones on the sea beach. [Illustration: _Birds. Pl. 19._ _Upercerthia dumetaria._ ] 2. OPETIORHYNCHUS PATAGONICUS. _G. R. Gray._ Patagonian Warbler, _Lath._ Syn. iv. p. 434. Motacilla Patagonica, _Gmel._ Motacilla Gracula, _Forst._ Draw. No. 160. Sylvia Patagonica, _Lath._ Index, ii. 517. Furnarius Lessonii, _Dumont_. —— Chilensis, _Less._ Voy. de la Coqu. i. p. 671, n. Tr. d’Ornith. p. 307, pl. 75, f. 1. Opetiorhynchus rupestris, _Kittl._ Mem. de l’Acad. St. Petersb. i. p. 188, pl. viii. Uppucerthia rupestris, _D’Orb. & Lafr._ Mag. de Zool. 1838, p. 21.