Genus PETROCINCLA. 
Gren. Cuar. Beak stout, straight, the ridge arched at the point. Nostri/s basal, round, partly 
covered with hairs. Wings of middle length; the first guéd/-feather very short, or almost 
spurious, the third the longest, the second a little shorter. Feet moderate, somewhat 
strong; the acrotarst and paratars: perfect. Tazl equal. 
Type of the genus, Turdus saxatilis, Linn. 
ROCK THRUSH. 
Petrocincla saxatilis, Vegors. 
Le Merle de Roche. 
Tue Rock Thrushes, of which the present may be taken as a good example, differ so much from the more 
typical birds of the family, in form as well as in habits, manners and the localities they frequent, as to justify 
their being raised to the rank of a genus. This was hinted at by M. Temminck, who formed them into 
a section, which section has been subsequently established as a genus by Mr. Vigors, under the name of 
Petrocincla. 
These birds, instead of dwelling in groves and woods,—a circumstance which so peculiarly characterizes 
the Thrushes in general,—affect the rugged and inaccessible declivities of rocks and mountains, for which 
their form is adapted ; the shortness of their tails and the length of tarsi indicating them to be among those 
birds which live more exclusively on the open ground. In many respects they manifest a relationship to the 
Saaicole, between which and the rest of the Merulhde they seem to constitute a link of union, forming also 
a close alliance with various groups of ground Thrushes from other portions of the globe. 
The present species is an inhabitant of the central and eastern portions of Europe, confining itself almost 
exclusively to the rocky and mountainous districts, especially the Alps, the Apennines, the Pyrenees, and 
some of the higher mountains in France. In such situations it incubates, constructing a nest of moss and 
herbage in clefts of the rock, among masses of loose stones, or in old ruins, laying four eggs of a pure greenish 
blue. M. Cuvier, in the short notice he gives of this bird in his Régne Animal, states that the male is distin- 
guished by its beautiful song ; but into any minute details respecting its manners and peculiarities, we do not 
profess ourselves able to enter, and it is a matter of regret, that those who have had so many opportunities 
of becoming acquainted with its habits, &c., in its native haunts, should have given us such meagre accounts 
respecting them. 
The examples which have come into our hands prove it to be a species that undergoes several remarkable 
changes of plumage, which we cannot better explain than by availing ourselves, in our text, of the description 
given by M. Temminck, who appears to have paid a close attention to the subject. 
‘In the adult male, the head and neck are of an ashy blue, darkening on the upper part of the back into 
black clouded with blue; below this a large white space extends as low as the upper tail-coverts, which are 
also black. The shoulders black; the quill-feathers dark brown ; the tail ferruginous red, except the two 
middle feathers, which are rufous brown ; the chest and whole of the under surface bright ferruginous, each 
feather, especially those of the inferior tail-coverts, being obscurely tipped with white ; beak blackish ; legs 
brown. Length seven inches and a half.” 
‘¢ The females have the whole of the upper parts brown ; on the back are several large whitish markings 
bordered with brown; the throat and sides of the neck of a pure white ;” but it often happens that the 
feathers of that part are edged with ashy brown ; the rest of the inferior surface is of a reddish white, with 
fine transverse bars at the tip of each feather; tail of a light red, with the two middle feathers of an ashy 
brown. 
The young of the year are, again, altogether different. The whole of the upper parts are ashy brown 
mottled with whitish grey; the end of each feather marked with a white spot; the quill-feathers and coverts are 
darker, the feathers forming the coverts having a grey border and whitish ends; tail red, lighter in colour 
at the extremity ; the under parts very similar in colour to those of the adult female, but with more of white 
varied with red, and a multitude of irregular markings of brown. 
Its food consists of Scarabzei and other insects, as well as wild berries. 
Our Plate represents a male and female in full plumage. 
