Mr. R. Collett on Phylloscopus borealis. 223 
during the summer I can find scarcely any variation in the 
coloration of the plumage; in some males the green colour 
may be somewhat more strongly developed than in others 
shot at the same time. 
As previously mentioned, these birds appear to arrive 
rather late in the spring. Mr. Seebohm, in 1877, 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 afterwards they were numerous. No information 
can be given concerning their departure. The last specimen 
shot by me was on July 28th (at the third nest), the day before 
I left the Tana; it had already commenced to moult, and had 
a considerable number of new feathers on its head and back. 
In conclusion I will give the measurements of sixteen 
freshly killed specimens shot by me in Finmark in 1878 and 
1885. 
Males. 
Total 
length. 
Wings. 
Tail. 
mm. 
mm. 
mm. 
a .... 
.... 140 
70 
49 
b .... 
.... 137 
70 
51 
G ... . 
.... 135 
73 
53 
d _ 
.... 135 
73 
52 
G . . . . , 
.... 135 
70 
49 
/ . 
.... 135 
69 
50 
9 . 
.... 133 
70 
48 
h . 
.... 132 
69 
43 
i . 
,... 132 
67 
45 
j . 
.... 131 
70 
53 
k . .. . 
.... 130 
68 
49 
1 . 
.... 129 
67 
48 
m . 
,... 127 
70 
50 
n .... 
.... 127 
69 
50 
Females. 
o . 
... 125 
67 
48 
p ... . 
... 124 
65 
49 
According to these measurements (together with those 
previously reported) the average length of this species will 
be, for males 132 millim., and for females 124 millim, 
Christiania, January 31, 1886. 
