The STONE THRUSHES, or ROCK WAGTAILS (Petrocincla), are comparatively large birds, recognisable by their slender body and strong, awl-shaped beak, which is broad at its base; the upper mandible is slightly arched, and curved at its tip; the tarsi are armed with very decidedly bent claws; the wing is long, its third quill exceeding the rest in length, while the tail is short, and almost straight at its extremity. The plumage is smooth, bright-tinted, and sometimes much variegated.
THE STONE THRUSH, OR ROCK WAGTAIL.
The STONE THRUSH, or ROCK WAGTAIL (Petrocincla-Turdus-saxatilis), is a magnificently-coloured bird, about eight inches long and fourteen broad. The head, face, part of the throat, nape, and rump are of a beautiful blueish grey, the entire under side is bright rust-red, the quills are blackish brown, the shoulder-feathers deep grey or slaty black; the two centre tail-feathers are dark grey, and those at the exterior rust-red. In autumn all the small feathers have light edges. The female is of a pale brown, spotted with a still lighter shade on the upper part of the body, whilst the rust-red feathers on the under side are darkly bordered: the throat is white. In both sexes the eyes are reddish brown, the beak pale black, and the feet of a reddish hue; the young resemble the mother. These birds frequent all the mountain regions of Southern Europe, but are also known to breed in some part of Austria, in the Tyrol, along the course of the Rhine, and occasionally in Bohemia and in the Hartz Mountains: in Italy and Greece they are especially numerous, and everywhere appear to prefer the rocky valleys lying immediately at the foot of mountain ranges to the precipices or towering heights occupied by the group last described.
The Rock Wagtails generally appear in Europe about April or May, and almost immediately commence their preparations for breeding. Their nests, usually concealed with great cunning in such holes in the rock or ground as are almost inaccessible, are made of twigs, straw, moss, or grass, heaped roughly together to form the outer wall, the cup-shaped interior being neatly lined with a variety of elastic materials, selected with great care. The delicate blueish green eggs (see Fig. 24, Coloured Plate IV.) are from four to six in number. We have not as yet been able to ascertain whether the male relieves his partner in the work of incubation, or contents himself with amusing her by a kind of dance, performed with ruffled streaming plumage and half-closed eyes, in which he delights to indulge at this season of the year. Both parents, however, assist in tending the young flock, who are reared on the same kinds of insects as form the staple food of the adults; the latter also devour snails and worms, and during the autumn consume large quantities of berries and fruit, including grapes. Their winter migrations take place in September, and often extend over a large portion of Northern Africa; indeed, we have often seen them in the vicinity of the Blue River. In disposition the Rock Wagtail is cautious, sprightly, and restless, passing almost the entire day in active exercise; its flight is extremely light and beautiful, and so rapid as to enable it to seize an insect on the wing; unlike most of the members of its family, it generally flies in a direct line, and, after describing a few circles in the air, hovers awhile before perching. Upon the ground its movements alternate between a tripping step, accompanied by repeated bowings of the head, and the dancing movement alluded to above. Its voice is pleasing, flute-like, and capable of imitating a great variety of notes and sounds; it is for this reason unusually attractive when caged. Count Gourcy tells us that it soon becomes so tame as to greet its master with a song, and testifies its affection by a variety of pretty tricks.
We must not omit to mention one strange propensity to which this species is addicted when in captivity, during the season at which its kind usually migrate. At that time of the year it seems seized with attacks of perfect frenzy, rushes round its cage, leaps about, and utterly refuses to take any food that is not forced upon it. This state of excitement only continues for from eight to ten days, and leaves the bird in its ordinary state of health. Throughout the whole course of the attack the little prisoner exhibits a degree of terror which is quite inexplicable, at sights and sounds that at other times would scarcely attract its attention.
THE BLUE ROCK WAGTAIL, OR BLUE THRUSH.
The BLUE ROCK WAGTAIL, or BLUE THRUSH (Petrocincla cyana), is rather larger than the species last mentioned, being from eight inches and three-quarters to nine inches and a half long, and fourteen broad; the wing measures five and the tail three inches and a half. The plumage of the male is of an uniform greyish blue, and the quills and tail-feathers edged with blue. The female is blueish grey upon the upper part of the body, the throat being decorated with light reddish brown spots, each of which is surrounded by a dark line; the feathers on the under side are edged with brownish white, and marked with dark brown crescent-shaped patches; the quills and tail-feathers are also dark brown. The nestlings resemble the mother, but have light brown spots upon the back; the eyes of all are brown, and the beak and feet black. After the moulting season all the feathers in the plumage of the male are of an uniform greyish blue, and the quills and tail-feathers edged with blue.
The Blue Thrushes inhabit the whole of Southern Europe, Northern Africa, and a portion of Central Asia, and are especially numerous in Greece, Dalmatia, Italy, the South of France, Spain, Egypt, and Algiers; during winter a few are occasionally seen in India, but these, no doubt, are stragglers that have lost their way, as, for the most part, these birds remain throughout the entire year in their native land. Like the species last described, they principally occupy rocky valleys and mountainous regions, but are also often to be seen about towns and villages, where they perch upon steeples, roofs, or lofty walls; in Egypt they frequently dwell within the ruins of ancient temples. Although sprightly and active, they are remarkably unsocial, and exhibit a positive dislike to the society not only of man and of birds in general, but of their own kind. During the period of incubation alone do they associate even in pairs; at other seasons each leads an entirely independent life, and exhibits active hostility to every other member of the feathered creation. The flight of this species is much more continuous than that of its congeners, and it usually hovers before perching: like the Thrush, it often soars into the air when about to pour forth its song. Upon the ground it moves with great ease and rapidity. The voice of the Blue Thrush, though inferior to that of the Rock Wagtail, is pleasing, and so flexible as readily to imitate the notes of other birds. The evolutions performed by the male for the delectation of his mate are even more comical than those indulged in by the Petrocincla saxatilis, as the little creature inflates his body until it is almost as round as a ball, bows his head, and continually brandishes his tail aloft whilst engaged in going through his dancing steps. The nest is situated in holes in rocks, walls, and ruins, or upon lofty towers or steeples, and is rudely formed of grass; nevertheless, its flat interior is neatly lined with fibres. The four oval-shaped eggs which compose a brood are laid at the beginning of May. These are of a glossy, greenish blue, faintly spotted with violet-grey, and more distinctly with reddish brown; unspotted eggs are also occasionally laid. In Italy, Malta, and Greece, the Blue Thrush is especially esteemed as a domestic favourite, and commands a high price. Wright tells us that in Malta particularly, from fifteen to twenty dollars are frequently paid for a good singer, and that as high a sum as fifty dollars has been given for an unusually gifted specimen. In Malta, such of the lower orders as keep these birds fasten a piece of red cloth to the cage, in order to protect its inmate from the much-dreaded evil eye. Owing to the extreme care with which the nests are concealed, and the unusual timidity displayed by this species, its capture is attended with great difficulty; indeed, none but the most wary and patient of sportsmen can hope to obtain an adult bird.
THE BUSH WARBLER.