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.