It is a stout little bird, about 8-1/2 to 9 inches long, with a slender, slightly-curved beak nearly an inch in length, and strong legs suited to its terrestrial habits. The upper plumage is uniform rufous-brown in colour, brightest on the tail; the under surface very light brown. It ranges throughout the Argentine Republic to Bahia Blanca in the south, and is usually named _Hornero_ or _Casera_ (Oven-bird or House-builder), but in Paraguay and Corrientes it is called _Alonzo Garsia_ or _Alonzito_. Azara could give no reason for such a name; but it seems to me that one need not look for one beyond the fact that this species inspires an affectionate admiration in the country people: I mean in those of _Spanish_ origin, for the bird-killing French and Italians have no tenderness for it. I have frequently been assured by natives that the Hornero is a _pious_ bird, and always suspends its labours on sacred days. With this pretty belief about it in their minds, it is not strange that in some districts they have called it by a human name. It is resident, pairs for life, and finds its food, which consists of larvæ and worms, exclusively on the ground. It delights in open places, where it can move freely about on the ground; and is partial to courtyards, clean garden-walks, &c., where, with head thrown back and bosom prominent, it struts along with an air of great gravity, lifting its foot high at each step, and holding it suspended for a moment in the air before setting it firmly down. I once saw one fly down on to a narrow plank about ten feet long lying out on the wet grass; it walked gravely to the end of the plank, then turned, and deliberately walked back to the other end, and so on for about twenty times, appearing to take the greatest pleasure in the mere act of promenading on a smooth level surface. When disturbed, the Oven-bird has a loud, monotonous note of alarm or curiosity, which never fails to bring all its fellows within hearing-distance to the spot. The movements of a fox, weasel, or cat in a plantation can always be known from the noisy turmoil among the Oven-birds. At frequent intervals during the day the male and female meet and express their joy in clear, resonant notes sung in concert--a habit common to a very large number of Dendrocolaptine birds, including, I think, all those species which pair for life. In a majority of species this vocal performance merely consists of a succession of confused notes or cries, uttered with great spirit and emphasis; in the Oven-bird it has developed into a kind of harmonious singing. Thus, the first bird, on the appearance of its mate flying to the place of meeting, emits loud measured notes, sometimes a continuous trilling note with a somewhat hollow metallic sound; but immediately on the other bird joining, this introductory passage is changed to rapid triplets, strongly accented on the first and last notes, while the second bird utters a series of loud