KENNICOTT'S WILLOW- WARBLER 333 



quarters in spite of a great extension of summer range. There can be 

 no reasonable doubt that the original home of the species was in the 

 more eastern part of Siberia, with winter quarters in southeastern 

 Asia and the Malay Archipelago. Yet the European birds have not 

 adopted what might seem the natural course of migrating for the 

 winter to Africa. They return annually to the much more distant 

 ancestral winter quarters, and to do this they must first travel the 

 long journey eastward to eastern Asia before finally turning southward 

 through the eastern parts of China. 



Throughout its summer range in the Old World this warbler is 

 primarily a bird of the northern birch woods, though it may also be 

 found nesting in conifer and mixed woods. In the Mount McKinley 

 National Park, however, the typical haunts of the species are the 

 spruce woods (Dixon, 1938). In northern Europe it is found as a rule 

 in well-grown woodland, avoiding the mere scrub growth which sat- 

 isfies its relative the willow-warbler (Phylloscopus trochilus), though 

 it also appears to require a fair amount of ground cover, and it has a 

 distinct liking for the neighborhood of streams or other water and 

 swampy places, though in no way confined to such. In fact, it may be 

 found in anything from dry woods to even those that are more or less 

 flooded. 



As there are next to no bionomical data on the species in America, 

 observations in Europe will be mainly relied on in the account that 

 follows, and as the writer has had the opportunity of studying Evers- 

 mann's warbler, as the Old World form is called, in Lapland it will be 

 possible to draw to a considerable extent on original experience. 



Migration. — The Arctic willow-warbler passes through eastern 

 China on its spring migration during the latter half of May and the 

 first 10 days of June. La Touche (1926) says that it "is one of the 

 last birds seen in the spring migration, being still seen in North-East 

 Chihli about the 10th of June. Although the song is never heard in 

 China, it commonly utters in spring a very loud call, 'tsic-tsic.' " He 

 says that it is "one of the earliest autumn migrants, appearing in 

 S. E. China as early as the last days of August and in North-East 

 China from the middle of that month." 



Collett (1886) says that, in Lapland, "these birds appear to arrive 

 rather late in the spring. Mr. Seebohm, in 1887, met with the first 

 arrivals on June 18th, and a few days afterwards found them in 

 considerable numbers. In 1885, at Matsjok (Tana), they could 

 hardly have arrived before June 22nd, but two or three days after- 

 wards they were numerous." At the other end of its summer habitat, 

 in northeastern Siberia, Thayer and Bangs (1914) say that this 

 species arrived at Nijni Kolymsk, May 30, 1912. 



Referring to the Commander Islands, to the westward from the 



