The Cassicinae, or Cassiques, are sometimes uniform black, sometimes black relieved by chestnut, yellow, green, or scarlet; the bill being frequently white, instead of the usual black or brown. The Agelaeinae are generally black, varied with red and yellow, Dolichonyx oryzivorus, the Bobolink, being, however, black, brown, buff, and white, with a duller plumage in winter. The Sturnellinae are brown, variegated with black; having scarlet or canary yellow under parts, and in Sturnella magna, the "Meadow-Lark," a black gorget. The Icterinae (all but one of which belong to the extensive genus Icterus) are glossy black, with yellow, bay, or orange patches–especially upon the rump and lower surface–and often some white on the wing. The Quiscalinae are black, occasionally with metallic gloss, and scarlet or brown markings. The females are commonly similar to the males, especially in the Cassicinae, but are sometimes comparatively sombre. Agelaeus phoeniceus, the "Red-winged Starling," several males of which have been captured in Britain, Icterus baltimore, the "Baltimore Oriole" and Quiscalus versicolor, the "Crow-Blackbird," are good examples of their respective groups. The curious resemblance of Sturnella and Macronyx has already been mentioned (p. [500]).
Fig. 142.–"Baltimore Oriole." Icterus baltimore. × ½.
Some of the Family are large birds for Passeres, Gymnostinops, for instance, being the size of a Rook; they are commonly gregarious, and frequent forests or wooded country, the Agelaeinae and Sturnellinae in particular preferring open grassy places and marshes, and all seeming fond of the neighbourhood of water. The Cassicinae only range from South Mexico to Paraguay and Bolivia; but the other Sub-families occupy most of America, except the extreme north, the Quiscalinae extending to Chili and Argentina, the Sturnellinae to Patagonia. Several species are peculiar to the Antilles. The flight is sufficiently strong and swift, flocks of Agelaeus and Quiscalus performing evolutions like Starlings; while these forms, Dolichonyx, Scolephagus, Xanthocephalus, and others roost in huge companies on migration. These lively, active, and fairly tame birds differ considerably in habits, Dolichonyx sitting continually on fences, clinging to plant-stems, or hovering in the air, Sturnella sailing or fluttering with jerky movements, the Icterinae and Cassicinae being particularly accustomed to perch, and many forms walking well or even gracefully. The members of the genus Icterus have melodious voices, those of I. vulgaris and I. baltimore being especially rich and varied; they are therefore favourite cage-birds. Dolichonyx, perhaps the finest of American songsters, often sings in chorus; Sturnella produces tuneful, wild, but not powerful notes; the Cassicinae utter loud discordant cries or sweeter strains; while many forms chatter, chuckle, squeak, scream, or whistle more or less harshly, whether in the air, in the trees, or on the ground. The food in the breeding season consists almost entirely of insects, their larvae, and small molluscs; but fruit is also eaten, and havoc wrought in maize- and corn-fields, Quiscalus even pulling up the shooting blades. The terrestrial species often scratch amongst the soil, but the Icterinae and Cassicinae rarely feed upon the ground.
The Agelaeinae build cup-shaped nests of grass, sedge, or rushes, sometimes lined with hair, in bushes or reeds, generally in damp or marshy spots; and lay five or six white, drab, greenish, bluish, or reddish eggs, with purple, black, red, or brown blotches, dots, and lines: the Quiscalinae deposit similar eggs in rougher structures of twigs, grass, and the like, placed in tree-forks or bushes. Both these groups often form societies. Sturnella hides its deep fabric in grass or rushes, the eggs being speckled rather than spotted; the Icterinae, or "Hang-nests," usually weave pensile nests of plant-stems, tendrils, grasses, or even rags, lined with wool, down, and so forth, which are rarely domed, and generally contain five or six eggs of a more delicate colouring than those of their kindred, varied by marblings, zigzags, streaks, and spots of brown, purple, black, or red. The Cassicinae commonly join in colonies and hang their elaborate, purse-like nurseries of grass or palm-fibres, Tillandsia, Bromelia, or lichens, lined with feathers, from branches above water; the two to five eggs are plain white, or greenish- bluish- or reddish-white, blotched, dotted, dashed, or scrawled with purplish- or reddish-brown and black.[[313]]
The gregarious Cow-birds (Molobrus), included in the Agelaeinae, lay eggs varying from white to pinkish, greenish, bluish, or brownish, often spotted or streaked with red, brown, and grey; one or more of these are by most species foisted in Cuckoo fashion upon other birds, the young of which disappear at an early date. It is a curious fact that M. rufo-axillaris is ordinarily parasitic on its congener M. badius, which itself seizes and uses other birds' nests. Many eggs are destroyed by the males, or are dropped promiscuously by the females, several of the latter often laying together. Cow-birds perch on cattle or follow the plough for insects, and utter ringing screams in concert.[[314]]
Fam. XXXVI. Fringillidae.–The Finches are small birds very closely allied to the Tanagridae and the Ploceidae; while the Buntings are here included in the Family, though often separated as Emberizidae. The most evident points of distinction in the last-named are the considerable deflection of the posterior portion of the angular gape and the bony knob often present on the palate; a gap, moreover, commonly occurs between the edges of the maxilla and the mandible. Extreme forms are thus easily recognised, but it seems almost impossible to draw an exact line of demarcation, even when the more Lark-like nest of Buntings and their streaky eggs are taken into consideration. The Fringillidae predominate in the Palaearctic Region, but are fairly plentiful elsewhere, except in the Australian Region, whence few are as yet recorded; many forms, however, have very limited ranges; while some are peculiar to certain islands, as Geospiza, Camarhynchus, and Cactornis to the Galápagos, Passer jagoënsis to the Cape Verds, Chaunoproctus to the Bonin Islands and Telespiza to the Laysan group, Nesospiza to Tristan da Cunha, Melopyrrha to Cuba, Rhynchostruthus and Passer insularis to Socotra.
The bill is usually stout and cone-shaped, often with a notched maxilla, occasionally with a ridged culmen; it is enormous in Geospiza, Camarhynchus, Chaunoproctus, and some other forms, and highly developed in Coccothraustes, Pyrrhula, and elsewhere; but is at times either remarkably short, or longer and more slender, as in Cactornis, Chrysomitris, and Carduelis. Frequently it is curved, with overhanging tip, while a peculiar crossing of the mandibles at their extremities marks the genus Loxia. An excessive summer growth has been especially noticed in Redpolls, which is worn down by hard food in winter. The beak is seldom abnormal in Buntings. The metatarsus is moderate; but in Calcarius, Plectrophenax, Nesospiza, and Chamaeospiza the hind claw is elongated, as is the mid-claw in Phonipara. The wings, which have a minute outer primary, vary from very long, as in Hesperiphona, to short as in Passer, and from pointed, as in Plectrophenax, to rounded as in Ammodramus; the secondaries are shaped like a bill-hook in Coccothraustes, while the inner are much lengthened in Emberiza fucata. The tail is fairly normal, but may be long or decidedly short, square, round, graduated, or forked; the rectrices are unusually acute in Spiza, Coryphospiza, and Emberizoïdes. Many species possess a crop. Bristles generally occur at the gape, and the nostrils are concealed by feathers or by a membrane.
Fig. 143.–House-Sparrow. Passer domesticus. × ⅖. (From English Illustrated Magazine.)