218 Mr. R. CoUett on Phylloscopus borealis. 



seas. Its northern boundary in our land may be said to be 

 70° 20', while, in Siberia, Mr. Seebohm did not meet with it 

 north of 69°. 



It was especially in the months of June and July 1885 

 that I had good opportunities of observing this species 

 during its summer residence in our latitudes. That year I 

 visited the wide Tana valley * ; and here I found P. borealis 

 everywhere about the lower course of the river (Matsjok, 

 Seida, Oldernses, Polmak), where the birch- woods were 

 tolerably luxuriant, and where the ground was not too dry, 

 but well overgrown with plants and grasses. In South 

 Varanger, where I have met it on several previous occasions 

 (in Langfjord and on the Pasvig river), I found it last 

 summer again in the old localities at Elvenses and Salmi- 

 Javre, and met with it also in Jarfjord. 



At several of these places, especially at Polmak, in Tana, 

 and at Salmi-Javre on the Pasvig, these birds were com- 

 paratively numerous, and during a few hours^ walk I have 

 met with a dozen singing males. 



As the luxuriant birch- woods are only to be found in the 

 larger valleys, these are the chief places of resort of this 

 species ; but they do not live on the plateaus or open places, 

 even when these are partially wooded, as the woods there are 

 generally more or less thin and the trees stunted. They 

 frequent both the birch trees and willow- thickets, and often 

 sit singing from the top of the tall fir trees which are to be 

 found singly or in small numbers in the birch-woods. In 

 its habits P. borealis resembles the other Phylloscopi, but is 

 wilder, flies with greater strength, and appears reluctant to 

 show itself so openly between the leaves as, for instance, 

 P. trochilus. They are often seen fluttering about the end 

 of the branches like the last-mentioned species in order to 

 look for insects. 



Concerning the breeding of P. borealis but little, so far as 

 I know, has yet been published. 



Near Lake Baikal, in 1866-71, Dybowski found it breeding 



* Lately described by Mr, Alfred Chapman in ' The Ibis ' for 1885, 

 p. 158, in his " Birds' -nesting Ramble in Lapland." 



