220 Mr. R. Collett on Phylloscopus borealis. 
no pains, in finding any nests. At least six males were 
singing continually throughout the whole day close to our 
station, Bornsund, at Salmi-Javre; but the females hardly 
ever permitted themselves to be seen, while the enormous 
swarms of mosquitos rendered any close observations almost 
impossible. We searched for two days unceasingly amongst 
the singing males. We found a number of other nests in 
the immediate neighbourhood, but obtained no evidence that 
nests of P. borealis lay near the spot where the males were 
singing. 
On June 25th I was again at Matsjok; and now, in the 
course of two days, I found three nests of this species, each 
containing half-grown young ones. At that time it was 
easy enough to find the nests, as we were attracted to the 
birds by their very peculiar call-note. The males had by 
this time almost ceased to sing, and it was now altogether 
difficult to discover the birds. A good way of finding them 
was to place one's self close to a nest of Fringilla monti- 
fringilla , and cause its owners to utter their loud calls of 
anxiety. This never failed to bring a number of the small 
birds of the district to the spot. One single sharp note of 
P. borealis and a glimpse of it between the leaves would be 
sufficient to show that its quarters were not far off*. Then I 
had to search for the place; and on getting near the nest, 
the parents exhibited great signs of anxiety, although they 
were sometimes cautious enough, and I was once obliged to 
wait patiently for two hours exposed to the attacks of the 
blood-thirsty mosquitos before the female would fly to her 
nest amongst the tall forest plants. 
The first nest I found (on July 27th) was placed at the foot 
of a slope thickly covered with birch trees, and was well 
hidden by Cornus suecica , halfgrown Chamcenerion angusti- 
folium , Veronica longifolia, and Melica nutans. It lay under 
the root of a tree, which partly formed a roof to the nest. 
The other nest, found the same day at another slope in the 
wood, had no such protection; but both nests were com¬ 
pletely domed, as is usual in those of the other Phylloscopi. 
They were most loosely constructed ; the outer base was 
