510 PASSERIFORMES CHAP. 
is usually moderate, being particularly strong in Geocichla, Neso- 
cichla, Zoothera, and Turnagra ; in Saxicola, Erithacus, and Daulias 
it is at once slender and elongated. Generally the anterior scales 
are fused together, forming an ocreated covering (p. 10), but the 
opposite sometimes occurs, as in Aecentor, Nesocichla, and Tham- 
nobia. Typically the wing is fairly long and broad, with abbreviated 
outer primary, the next feather being emarginated in some species 
of Myrmecocichla ; bat mm Dr. Sharpe’s group Thamnobiae,’ it is 
generally abbreviated and more rounded, in Stadia it is pointed. 
The tail may be long and wide, as in 7urnagra, or comparatively 
short, as in Monticola and Pratincola, but is usually of medium 
length; it is normally square or rounded, though emarginated in 
Stalia, and much graduated in Copsychus and Cittocincla, while in 
Cossypha natalensis 1t has pointed feathers.  Zurdus (Geocichla) 
varius, T. horsfieldi, and 7. hancw have fourteen rectrices. 
The coloration is ordinarily plain black or brown, more or 
less varied with grey, white, rufous, or chestnut, occasionally in 
the form of a collar; many Thrushes, moreover, exhibit the charac- 
teristic white breast spotted with brown. The bill is frequently 
orange or yellow. As examples of the genus Z’urdus we may take 
our native Blackbird, Mistletoe- and Song-Thrushes 7. merula, 
7. viscivorus, and 7. musicus ; our summer visitor the Ring-Ousel, 
7. torquatus ; our winter nnmigrants the Redwing and Fieldfare, 
7. iliacus and 7. pilaris ; the American “ Robin,” 7. migratorius ; 
and the Ground-Thrushes (“Geocichla,’) with their hght patch under 
the wing. The sexes are commonly alike, but black or grey males 
have usually brownish females. A bushy crest occurs in Catharus. 
Of some ten Rock-Thrushes (Monticola), M. saxatilis occurs 
exceptionally in Britain. It has a cobalt and blackish-blue head, 
neck, and upper back, a nearly white mid-back, brown remiges, 
chestnut lateral rectrices and lower surface. JZ. cyanus is almost 
entirely blue. The browner hens are generally spotted and barred 
below. Cochoa viridis is green and black, with blue-green under 
parts, and blue on the head, tail, and wings; C. purpurea has” 
the bright colours replaced by purplish-brown and lavender; C. 
azurea 1s mainly rich blue, becoming purple below. The females 
are duller. Blue-birds (Stalia) are bright blue, often with chest- 
nut breast or back, the males being the most brilliant ; Grandala 
caelicolor 1s indigo, with blackish wings and tail. 
1 Placed under the Timeliidae in Cat. Birds Brit. Mus. vii. 1883, p. ix. 
