The nest is usually placed between the angle formed by a small branch and the bole of the tree, and is a deep, well-made structure composed of many materials, and lined with horsehair, down, or feathers. The eggs are five, very small for the bird, pure white, and so frail that it is not easy to take them from the nest without breaking them.

While engaged in building, the birds constantly utter a low, soft, trilling note; and when the nest is approached they break out into long, somewhat reedy notes, resembling those of the Canary, expressive of alarm or curiosity.

88. CHRYSOMITRIS ATRATA (d'Orb. et Lafr.).

(HALF-BLACK SISKIN.)

+Carduelis atratus+, _d'Orb. Voy., Ois._ p. 364, t. 48. fig. 2.

+Chrysomitris atrata+, _Burm. La-Plata Reise_, ii. p. 490 (Mendoza); _Sharpe, Cat. B._ xii. p. 212.

_Description._--Black; concealed shoulder-spot, broad band on wing, basal half of tail-feathers, belly, and under tail-coverts bright yellow; bill and feet horn-colour: whole length 54 inches, wing 29, tail 18.

_Hab._ Bolivia and N.W. Argentina.

Dr. Burmeister obtained two examples of this species in the Sierra of Uspallata near Mendoza.

89. SYCALIS PELZELNI, Scl.

(YELLOW HOUSE-SPARROW.)

+Sycalis pelzelni+, _Scl. Ibis_, 1872, p. 42; _Scl. et Salv.

Nomencl._ p. 34; _Durnford, Ibis_, 1877, p. 172 (Buenos Ayres).

_Description._--Above yellowish olive-green, the back spa.r.s.ely striped with blackish; wing- and tail-feathers black, edged with yellow; forehead bright orange, the rest of the head like the back; below bright yellow; under surfaces of wings and tail also yellow: total length 54 inches, wing 27, tail 22. _Female_ dull brownish grey mottled with blackish above; under surface whitish grey, striped with dusky brown on the breast; wing- and tail-feathers edged with yellow.

_Hab._ S. Brazil, Paraguay, and Argentina.

The Yellow "House-Sparrow," as this species is called, is the town-bird of Buenos Ayres, but does not multiply greatly, nor is he familiar with man, like his rough, sooty-plumaged, far-away London relation.

The forehead of the male is bright orange, the prevailing colour of the entire plumage yellow, clouded with other hues. The female is grey, marked with pale fuscous, and is less in size than her mate. They remain with us all the year and live in pairs, the s.e.xes in this species being faithful. Sometimes they are seen a.s.sociating in small flocks, but I am inclined to believe that only the young unmated birds are gregarious. In 1867-8, during the cholera epidemic in Buenos Ayres, the Sparrows all disappeared from the town, and I was told by the manager of a large steam flour-mill in the town that the birds had not gone away, but had died. They were found dead all about the mill where they had been very abundant. My informant was a careful observer, and I have no doubt that he was correct in what he told me.

In spring and summer the male sings frequently with great energy, but without much melody. After a hurried prelude of sharp chirps and trills, he pours out a continuous stream of sound, composed of innumerable brief notes, high and shrill as those of a bat, wounding the ear with their excessive sharpness, and emitted so rapidly that the whole song is more like that of a cicada than of a bird. This piercing torrent of sound is broken at intervals by a long grave note, or half a dozen short rapid notes in a lower key, which come as an agreeable relief.

In towns they build in walls, like the English Sparrow; in country places they always select the domed nest of some Dendrocolaptine species to breed in. Possibly in some districts where I have not been, this Sparrow selects other breeding-sites; my experience is that outside of a town it never lays anywhere but in some domed nest, and at home I frequently put up boxes for them in the trees, but they would not notice them, though the Wrens and Swallows were glad to have them. Sometimes they make choice of the large fabric of the _Anumbius acuticaudatus_, called Lenatero in the vernacular; but their claim to this nest (even when the Lenateros are out of it) is frequently disputed by other species which possess the same habit as this Sparrow, but are more powerful than he. Their favourite breeding-place is, however, the solid earthen structure of the Oven-bird; and it is wonderful to see how persistently and systematically they labour to drive out the lawful owners--birds so much larger and more powerful than themselves. Early in spring, and before the advent of the Tree-Martins, the pair of Sparrows begin haunting the neighbourhood of the oven they have elected to take possession of, usually one pretty high up in a tree. As the season advances their desire towards it increases, and they take up their position on the very tree it is in; and finally a particular branch near the oven, commanding a good view of the entrance, is chosen for a permanent resting-place. Here they spend a great portion of their time in song, twitterings, and loving dalliance, and, if attentively observed, they are seen with eyes ever fixed on the coveted abode. As the need for a receptacle for the eggs becomes more urgent they grow bolder, and in the absence of the owners flit about the oven, alight on it, and even enter it. The Oven-bird appears to drive them off with screams of indignation, but the moment he retires they are about it again, and, even when it contains eggs or young birds, begin impudently carrying in feathers, straws, and other materials for a nest, as if they were already in undisputed possession. At this stage the Tree-Martins (_Progne tapera_) perhaps appear to complicate matters; and even if these last comers do not succeed in ousting the Oven-birds, they are sure to seize the oven when it becomes vacant, and the Sparrows, in spite of their earlier claim, are left out in the cold. But they do not take their defeat quietly, or, rather, they do not know when they are beaten, but still remain to harra.s.s their fellow-pirates, just as they did the Oven-birds before, bringing straws and feathers in their beaks, and when forced to drop these materials and chased from the neighbourhood with great noise and fury by the Tree-Martins, it is only to return undaunted in a few minutes, bringing more straws and feathers.

This Sparrow makes a rather large nest, neatly lined with horsehair, and lays five eggs, long, pointed, the entire surface thickly marked with deep chocolate-brown.

In rural districts this species is comparatively rare, not more than one or two couples being seen about each habitation; and I scarcely think it would be too much to say that there are four or five thousand Chingolos for every individual Yellow Sparrow. Yet it is a hardy little bird, well able to hold its own, subsists on the same kind of food and lays as many eggs as the _Zonotrichia_; and it possesses, moreover, a great advantage over the dominant species in placing its nest out of the reach of the parasitical _Molothrus_, the destroyer of about fifty per cent. of the Chingolo's eggs. I can only attribute the great disparity in the numbers of the two species to the fact that the Yellow House-Sparrow will breed only (out of towns) in nests not easily taken, and to the stubborn pertinacity which leads it to waste the season in these vain efforts, while the other species is rearing its brood. This is a blunder of instinct comparable to that of the Minera (_Geositta cunicularia_), mentioned by Darwin in the 'Voyage of a Naturalist,' where the bird made its hole in a mud wall a few inches wide, and on coming out on the other side simply went back and made another hole, and then another, unable to understand that the wall had not the requisite width.

In such a case as the Yellow House-Sparrow presents, in which the colour of the s.e.xes differs, the female being without any of the brighter hues found in the male, and which makes an elaborate nest and lays deeply-coloured eggs, it is impossible not to believe that the bird originally built in exposed situations, and subsequently--perhaps in very recent times--acquired the habit of breeding in dark holes. The frequent destruction of the exposed nest, and an abundance of vacant domed nests, into which some individuals occasionally penetrated to breed, would lead to the acquisition of such a nesting-habit; for the birds inheriting it would have an advantage and be preserved, while those persisting in the old habit of building exposed nests would perish. Domed nests made by Dendrocolaptine birds are very abundant even now, and it is probable that, before the country became settled by Europeans, they were very much more numerous. Darwin, speaking of the Oven-bird's habit of always placing its oven in the most conspicuous and (to man) accessible places, predicts, and truly I believe, that this habit will eventually cause the extinction of the species; for when the country becomes more thickly settled, the bird-nesting boys will destroy all the ovens. Probably when the Oven-birds were more abundant the Sparrows could always find vacant ovens to breed in, until a habit of breeding almost exclusively in these safe and convenient bird-built houses was acquired; and the present seemingly stupid persistence of the birds in struggling to get possession of those already occupied by stronger species, only shows that the habit or instinct has not been modified to suit a change in the conditions--_i. e._ a diminishing number of ovens to breed in, with, perhaps, the increase of other stronger species possessing the same habit. But while the instinct thus survives too strongly in the country birds, many individuals have taken to a town life, and acquired the new habit of breeding in holes in brick walls. Probably this race of town birds will eventually colonize the rural districts, and usurp the place of the country birds, which will then be placed at a disadvantage.

90. SYCALIS LUTEA (d'Orb. et Lafr.).

(YELLOW SEED-FINCH.)

+Sycalis chloropis+, _Burm. La-Plata Reise_, ii. p. 489 (Mendoza and Catamarca), +Sycalis lutea+, _Scl. Ibis_, 1872, p. 46, pl. ii.

fig. 2.

_Description._--Dark yellow; rump and body below brighter; wings and tail brownish black, edged with yellow; under wing-coverts pale yellow; inner margins of wing-feathers pale brown: whole length 55 inches, wing 32, tail 21. _Female_ similar, but duller and more brownish.

_Hab._ Andes of Peru, Bolivia, and Argentina.

Prof. Burmeister obtained examples of this species near Mendoza. In my revision of the genus published in 1872, I referred the specimens (upon some of which Prof. Burmeister based his species _S. chloropis_) to _S.

uropygialis_. I now find that this was an error, and that they really belong to _S. lutea_.--P. L. S.

91. SYCALIS LUTEOLA (Sparrm.).

(MISTO SEED-FINCH.)

+Sycalis luteola+, _Scl. Ibis_, 1872, p. 44; _Scl. et Salv. Nomencl._ p. 85; _Durnford, Ibis_, 1877, p. 172 (Buenos Ayres), et 1878, p.

394 (Centr. Pat.); _Barrows, Bull. Nutt. Orn. Cl._ viii. p. 132 (Entrerios). +Sycalis luteiventris+, _Burm. La-Plata Reise_, ii.

p. 489.

_Description._--Above light olive-green, marked with dusky stripes; wing-feathers blackish, with pale brownish edges; tail-feathers the same; beneath, throat and chest dusky buff, lower breast and belly yellow; bill and feet horn-colour; total length 50 inches, wing 26, tail 20. _Female_ similar, but not so bright.

_Hab._ S. America, from Colombia to Chili.

This is a slender, graceful bird, less than the Canary in size, the whole upper plumage yellowish olive, with dun markings, the lower surface of a dull yellow. The female is a little smaller than the male, and her colours are somewhat dimmer.

This species is resident and gregarious in the Argentine Republic, and in autumn frequently congregates in flocks of several thousands.

They are not so universally distributed as the Chingolo, and are not wood-birds, but frequent open plains abounding in thistles and other coa.r.s.e herbage, which affords them shelter. In cultivated districts, where their food is most abundant, they are excessively numerous, and, after the harvest has been gathered, frequent the fields in immense flocks. While feeding, the flocks scatter over a large area of ground, being broken up into small companies of a dozen or more birds, and at such times are so intent on their food that a person can walk about amongst them without disturbing them. They take flight very suddenly, bursting into a thousand chirping, scolding notes, pursue each other through the air, and, after wheeling about the field for a minute or two, suddenly drop down into the gra.s.s again and are silent as before.

In August they begin to sing, here and there an individual being heard in the fields; but when the weather grows warmer they repair to the plantations in vast numbers, and, sitting on the branches, sing in a concert of innumerable voices, which produces a great volume of confused sound, and which often continues for hours at a time without intermission.

By-and-by these pleasant choirs break up, the birds all scattering over the plains and fields to woo and build, and it is then first discovered that the male has a peculiar and very sweet song. Apart from his fellows, he acquires a different manner of singing, soaring up from his stand on the summit of a bush or stalk, and beginning his song the moment he quits his perch. Ascending, he utters a series of long, melodious notes, not loud, but very distinctly enunciated and increasing in volume; at a height of fifty or sixty yards he pauses, the notes becoming slower; then, as he descends with a graceful spiral flight, the wings outstretched and motionless, the notes also fall, becoming lower, sweeter, and more impressive till he reaches the earth. After alighting the song continues, the notes growing longer, thinner, and clearer, until they dwindle to the merest threads of sound, and cease to be audible except to a person standing within a few yards of the songster.

The song is quite unique in character, and its great charm is in its gradual progress from the somewhat thick notes at the commencement to the thin, tremulous tones with which the bird returns to earth, and which change again to the excessively attenuated sounds at the end.

The nest is deep, well-built, and well-concealed, sometimes resting on the ground, but frequently raised above it. It contains five long, pointed eggs, with a white or bluish-white ground-colour, and thickly spotted with brown. I have, frequently found the eggs of the _Molothrus_ in its nest, but have never been able to see this Sparrow feeding, or followed by, a young _Molothrus_. Possibly, if it ever hatches the parasitical egg at all, the voracious young Cow-bird is starved by the delicate food supplied by its foster-parents.

92. OROSPINA PRATENSIS, Cab.

(MEADOW SEED-FINCH.)

+Orospina pratensis+, _Cab. Journ. f. Orn._ 1883, p. 108, tab. i.

fig. 1.

_Description._--Cap dark greenish yellow; rump yellowish green; remainder of upper parts dark brown, feathers of interscapulium and of wings and tail edged with yellowish green; inner webs of the outer pair of tail-feathers almost wholly white, the next pair with a large white spot; under surface yellow, lightest on the throat, middle of belly, and crissum; flanks greenish: total length 45 inches, wing 25, tail 18.

_Hab._ Tuc.u.man.

Herr Schulz discovered this little Finch, which Dr. Cabanis has referred to a new genus allied to _Sycalis_, upon the high Sierras of Tuc.u.man, where it was observed sitting on the stones.