PHTLLOSCOPUS TROCHILUS 103 



do SO in some of the Atlas districts, where the climate and surround- 

 ings would appear to be suited to the bird's requirements. The species 

 occurs in Algeria and Marocco in autumn, winter and spring. The 

 Chiffchaff is to be met with in most of the wooded and cultivated 

 districts of Northern and Central Tunisia, and also in the oases of the 

 south. Gardens and orchards are much frequented by these little 

 birds, which may constantly be observed, in small parties of three or 

 four individuals, busily engaged in searching for aphides and small 

 insects. Lakes and ponds are also favourite resorts of this and the 

 following species, on account of the numerous gnats and small flies 

 generally plentiful in such spots. Winged insects are captured flying, 

 and it is a pretty sight to see the birds hawking for their prey, after 

 the manner of the Muacicapidce. A strand of wire stretched across a 

 pond or other piece of water is a great attraction, forming an excellent 

 point of vantage from which the birds can pounce down upon their 

 prey, and at times quite a large number of them may be seen con- 

 gregating together in such a spot. The PhijUoscopince, however, also 

 take their food on the ground, and may often be seen picking up small 

 insects on pathways. Although restless and constantly on the move, 

 the Chiffchaff is by no means shy and may easily be approached. Its 

 peculiar song resembling the words " chiff chaff," repeated many times 

 in succession, has given rise to the bird's English name. 



PHYLLOSCOPUS TROCHILUS (Linnseus). 

 WILLOW- WEEN. 



Motacilla trochilus, Linn. Syst. Nat. i, p. 338 (1766). 



Phylloscopus trochilus, Boic, Isis, 1826, p. 972 ; Scebohm, Cat. Birds 



Brit. Mus. V, p. 56 ; Whitaker, Ibis, 1895, p. 95 ; Eiianger, J. f. 0. 



1899, p. 257. 

 Sylvia (Ficedula) trochilus, Malherbe, Fauna Oniith. dc I'Alg. p. 13, 



(1855). 

 Phyllopneuste trochilus, Loche, Expl. Sci. Alcj. Ois. i, p. 252 (1867) ; 



Eoenig, J. f. 0. 1888, p. 192 ; id. J. f. 0. 1892, p. 390. 



Description. — Adult male, spring, from Oum-Ali, South Tunisia. 

 Above olive-green, slightly darker on the crown, and paler on the rump ; 

 quills and tail-feathers brown, margined with yellowish-green ; a superciliary 



