Adult male in winter plumage. Differs from the summer dress in being much, darker, this appearance being 

 caused by brown edgings to the feathers. 



Female. Above greyish brown, with a dull blue lustre on the lower back and rump, the feathers of the head 

 darker in the centre, giving a slightly mottled appearance ; general colour of the under surface of the 

 body buff with a dash of rufous, the feathers of the throat being almost uniform buff, those of the 

 cheeks and breast buff in the centre with brown edgings, the form of these plumes seeming rather 

 lanceolate in shape, the feathers of the lower breast and abdomen buff with brown edgings, but more 

 escalloped in appearance ; the flanks greyish ; qudls and tail coloured as in the male, but browner, and 

 with only a slight shade of blue on the wing-coverts ; bill and feet black. Total length 9 inches, 

 culmen TO, wing 4'8, tail 3"4, tarsus 1"1. 



Obs. The fully adult female is exactly like the male. 



Young male in first autumn. Bluish, varied here and there with whitish tips to the feathers, all the young 

 plumes being very downy in texture, grey in colour with a buff centre as in the old female ; all the 

 white-tipped feathers having a blackish shaft and a black line before the white apex ; all the feathers 

 which are being donned are shaded with brownish, as in the winter plumage of the adult ; the wing- 

 coverts and secondary quills tipped with white. 



Male of the previous year in spring dress. Blue, like the adult male, but always showing either on the back 

 or breast some traces of the white margins of the young plumage. 



Obs. In order fully to understand the differences of plumage above described, it may be as well to review 

 the successive changes through which both sexes of the present species pass before gaining their adidt 

 livery. We have never had the opportunity of personally examining a nestling ; but the young in down 

 are figured by Bettoni in the great work the 'Birds of Lombardy;' and they are there stated to be 

 spotted when in the nest. In that case both males and females must be very similar. But they do not 

 long remain alike ; for we have a young male in our collection, lately sent by Dr. Kriiper from Mace- 

 donia, and killed by that excellent collector on the 22nd of August, 1870, which is in a state of change, 

 and clearly proves that the young male of the Blue Rock-Thrush has even thus early in the autumn 

 begun to assume the blue garb of the mature bird. This is done by a direct moult, the downy buffy- 

 white feathers being shed and blue ones donned ; these latter have a white edging, before which runs a 

 black line ; and most of the feathers are shaded with brownish, as in the winter plumage of the adult. 

 By the following spring, when the brown shade to the feathers disappears, it is doubtful whether the 

 white edgings to the feathers are entirely lost, especially on the belly, which seems to be the last place 

 where they disappear. The old male, however, has no trace of these white margins, but is blue above 

 and below, becoming more brilliant in summer, and in winter assuming brownish edgings to the 

 feathers, which give it a dingy appearance. 

 With the female, however, the case is quite different ; and it was some time before we could identify the 

 mature female of this species. Scarcely two of our friends, who had seen the birds alive, agreed in 

 their description of the hen ; some assured us that the sexes were alike, while others said that the male 

 was blue while the female was spotted. Both these accounts are doubtless true; for we have a good 

 series now before us, from which it would appear that the female takes a much longer time than the 

 male to reach the adult stage of plumage. Thus both sexes are spotted in the nest ; but whereas the 

 male has put on his blue livery by August, the female still retains her spotted dress, and would appear 

 to breed in it the second year, as a specimen procured by Mr. C. A. Wright in Malta, in the autumn 

 of 1866, proves. The plumage of this specimen is much worn, the quills being pale brown, lighter at the 



