THE SPARROW-HAWKS. 143 



The brown shade on the bars of the under surface is a sign 

 of immaturity, and as the bird gets older, the rufous increases, 

 and the bars get less and less distinct, till the under-parts are 

 almost entirely rufous. This, however, is only the case in ex- 

 tremely old individuals. 



Adult Female. Larger than the male, and rather lighter grey ; 

 below whitish, with ashy bars, narrower than in the male, and 

 having a large tuft of downy rufous feathers on the flanks. 

 Total length, 15-5 inches; wing, 9-5; tail, 7-0; tarsus, 2-5. 



Young Birds. General colour above sepia-brown, all the 

 feathers margined with rufous, especially on the crown ; occi- 

 put and nape mottled with white ; a distinct eyebrow, cheeks 

 and ear-coverts, white, streaked with blackish, the hinder mar- 

 gin of the ear-coverts brown, washed with rufous \ quills brown, 

 barred across with darker brown, more distinct on their lower 

 surface ; tail ashy-brown, with whitish tips, and crossed with 

 five bars of darker brown ; under surface of body white, the 

 throat narrowly streaked with black, the fore-neck and chest 

 with broad rufous streaks, the flanks and thighs distinctly barred 

 with dark brown ; under tail-coverts white ; under wing-coverts 

 buffy-white, with numerous spots or bars of dark brown ; iris 

 pale yellow. 



It takes some time before the young birds attain the adult 

 plumage, and it is certain that they breed while still in the im- 

 mature plumage. The first adult dress with bars underneath 

 teems to be gained by the breaking up of the pattern on the 

 feather, rather than by a complete moult. The feathers on the 

 chest have, in the first stage of plumage, a broad longitudinal 

 centre of pale rufous, and, as time goes on, this alters in shape 

 and breaks off into bars, the colour being distributed laterally 

 instead of longitudinally, and the rufous colour giving place to 

 dark brown. Thus two brown bars may be seen on a feather, 

 while the terminal one may be represented by a heart-shaped 

 spot of light brown, with a rufous " eye," the last remains of 

 the streak of the immature plumage, and when this spot of 

 rufous is at last absorbed, and the brown bars complete, the 

 bird shows the first stage towards the adult plumage. The next 

 change is by a moult, which seems to take place at irregular 

 seasons, and not in the first autumn, as with most birds, and 



