2. PHYLLOSCOPUS. 41 



Plivllopneuste kennicotti, Baird, Trans. Chicago Ac. Sc. i p 313 



pi XXX. fig. 2 (1869). ^ 



Sylvia sylvicultrix {Swinhoe), Gray, Hand-l. B. i. p. 216. no 3054 



(1869). 

 Sylvia borealis (Bias.), Gray, Hand-l. B. i. p. 216. no. 3063 (1869). 

 Phyllopneuste eversnianni, Bonap. apud Alston & Harvie Brown. 



Ibis, 1873, p. 61. ' 



Phyllopneuste javanica, Bonap. apud Salvad. Ucc. Born. p. 244 



(1874). ^ 



Phyllopseuste borealis {Bias.), Meves, Journ. Orn. 1875, p. 429. 



Spring plumage. General colour of the upper parts olive, some- 

 what yellower on the rump ; eye-stripe well defined, narrow, 

 greyish white, extending well onto the nape ; lores and the fea- 

 thers hehiad the eye to the nape dark olive; wing-coverts olive, 

 the median wing-coverts with narrow, and the greater wing-coverts 

 with broad, well-defined greyish-white tips, forming two pale bars 

 across each wing ; quills brown, narrowly tipped with greyish 

 white, ihe outside web edged with yellowish green, entirely absent 

 on the second primary, considerably marginated on the third aiid 

 fourth, and perceptibly so at the tip of the fifth; tail-feathers 

 brown, the outside web margined with yellowish green, and the 

 inside webs, except those of the two centre feathers, with a narrow 

 well-defined greyish-white margin. General colour of the under- 

 parts nearly white, greyer on the breast and flanks, and slightly 

 suffused with yellow, principally on the breast and flanks ; axil- 

 laries, under wing-coverts, and thighs pale yellow ; inner margin 

 of quills nearly white. Bill Acrocephaline, upper mandible dark 

 brown, under mandible pale. Legs, feet, and claws brown. Third 

 and fourth primaries longest ; second primary intermediate in 

 length between the fifth and sixth ; bastard primary very small, 

 thej^xposed part measuring 0-3 to 0-35 inch in adults, and 0-4 to 

 0-45 in birds of the year. Length of wing, male 2-7 to 2-o5 inches, 

 female 2-o5 to 2-4; tail, male 2-0 to 1-9, female 1-9 to 18; culmen 

 0-45 to 0-55 ; tarsus 0-S to 0-7. 



Summer plumage. The colour of the upper parts becomes greyer, 

 the yellowish-green edges to the wing and taii-feathers almost dis- 

 appear; the pale tips vanish, the bars across the wings become in- 

 distinct, and most of the yellow disappears from the underparts. 



Autumn pilumage. Similar to the spring plumage in minor details, 

 but yellower, the underparts being slightly suffused all over with 

 pale greenish yellow. Eye-stripe pale greenish yellow. 



Winter p>lumage. Similar to the summer plumage, but slightly 

 yellower. 



The Arctic Willow-Warbler breeds in the north of the Palcearctic 

 Eegion from Finmark, across Asia to Alaska, towards the northerly 

 limit of forest-growth, and in a similar climate in the subalpine 

 districts of South-easteni Siberia and Mongolia. It passes in 

 great numbers on migration in spring and autumn along the coast 

 of China and Formosa, and winters in the islands of the Malay 

 archipelago, Malacca, Tenasserim, and the South-Andaman islands. 

 An accidental straggler has been shot on Heligoland. 



