36 
ARCTIC TERN. 
The eggs are two or three in number, rarely four; they 
are subject to almost endless variety, the ground colour being 
variously white, green, dull green, brown, pale blue, and pale 
yellow, spotted with grey and dark reddish brown. They 
are usually laid the beginning of June. The period of incu¬ 
bation is about fifteen or sixteen days. 
Male; length, one foot three inches; bill, coral red, with 
sometimes a little blackish red at the tip: head on the sides 
below the eyes, white; forehead, crown, and neck on the back, 
deep black, ending in a rather rounded peak; nape, white. 
Chin, white; throat, pale grey; breast, grey; back, rather dark 
grey above, below white. The wings, when closed, reach to 
the end of the tail; greater and lesser wing coverts, grey; of 
the primaries, the first has the outer web dark leaden grey, 
nearly black, except the tip, which is grey; the others have 
the outer webs and half of the inner dark grey, the shafts 
white, the tips grey. The tail, deeply forked, has the two 
longest feathers on each side dark grey on the outer webs, 
the others white; upper tail coverts, white; under tail coverts, 
pale bluish grey. Legs, short, feathered to the knee joint, 
and, as the toes, deep red; claws, dusky black; webs, deep 
red. 
The female is a little less than the male, and the black 
extends rather farther down the nape. 
The young are at first covered with yellowish grey down, 
mottled with darker. In their first year, they have the bill 
red, the ridge of the upper mandible and the tip dull brown. 
Forehead, dull white; crown, a mixture of black and white, 
or grey; back of the head, neck on the back, and nape, dusky 
greyish black; the sides of the head below the eyes dull white; 
chin, throat, and breast, dull white. Back, bluish grey, mottled 
with crescent-shaped bars of brownish black on each feather, 
the tips pale yellowish grey; greater and lesser wing coverts, 
bluish grey, barred with crescent-shaped marks on the feathers 
of dusky black, and tipped with white; of the primaries, the 
first is leaden grey on the outer web, the others bluish grey, 
the inner webs of all nearly white; secondaries, dull bluish 
grey, barred with dusky black of a crescent-shaped form on 
each feather, and tipped with white; tertiaries, tipped with 
white; greater and lesser under wing coverts, white. The tail 
has the outer webs of the three long feathers on each side 
slate grey; upper tail coverts, white; legs and toes, pale 
orange red; claws, dusky; webs, pale orange red. 
