338 BULLETIN 196, UNITED STATES NATIONAL MUSEUM 



unusually quickly, fourteen to sixteen times in succession. After each song 

 follows a short period of rest, which in the height of the singing-time scarcely 

 exceeds half a minute, when it recommences its song again. 



The song of the different specimens was almost precisely alike, but in some it 

 might sound a little more or less harsh than in others. Seebohm has compared 

 the song to the trill of the Redpole; and this seems to be a suitable description, 

 although it appeared to me to resemble more the first quick notes of the song of 

 Sylvia curruca. 



In these latitudes, where the day is but little lighter than the night, the song 

 might be heard at any hour and even at midnight. A little after the middle of 

 July most of the males had ceased to sing, although at Matsjok once or twice I 

 heard the song so late as the 28th of that month. 



Field marks. — A small warbler something like a warbling vireo, 

 about 4% inches long, with dull greenish upperparts, a prominent 

 pale yellowish eye stripe, whitish underparts tinged with yellow and 

 a narrow pale wing bar. In birds on the breeding ground I found 

 this bar tolerably noticeable at close range, but not otherwise. As 

 the season advances it may be much obscured by abrasion. In the 

 breeding season the peculiar song and note are additional good 

 characters. 



Fall and winter. — This species leaves its breeding grounds early, 

 and La Touche (1926) states that it appears in southeastern China 

 as early as the last days of August and in northeastern China from 

 the middle of that month. He states that on migration "it is quite 

 arboreal in its habits, except perhaps while passing through poorly- 

 wooded country, where I have seen it hunting for insects in grass and 

 bushes. But, once in a garden, I actually saw one hopping about on 

 an open gravel path." H. C. Robinson (1927) states: 



This little willow-warbler is very common * * * throughout the Malay 

 Peninsula, from August to the beginning of June, though very few arrive before 

 the middle of October or remain after April. Most of our visitors seem to remain 

 on or near the coast and do not penetrate into heavy jungle, though we have found 

 them near the summit of Kedah Peak, at a height of 3,500 ft. in December. 



Among the mangroves and Casuarinas on the coast they are often met with, 

 in small flocks or singly, and are very active and restless, flying with a short, 

 jerky action, and returning to their perch like a flycatcher. They seem to feed 

 largely on very small flies and midges, though they are often seen searching the 

 boughs like a tit. 



DISTRIBUTION 



Breeding range. — The principal Old World race A. b. borealis 

 (Blasius) breeds in northern Europe and Asia north to the tree limit 

 (generally around latitude 70° N., but to 75° on the Taimyr Peninsula), 

 including north Norway, north Finland (south to about 68°), north 

 Russia, and west Siberia south to about 61°, but in Siberia east of 



