78 BRITISH BIRDS, WITH THEIR NESTS AND EGGS 
many as ten. They are large, slightly oval, rather rough in grain, and are pure 
white, measuring from 2°44 to 2°1 inches by from 1°84 to 1°68 inches. They are 
laid at irregular intervals and, as in the case of some other Owls, the first hatched 
Owlets assist in incubating the later eggs. 
The Snowy Owl only migrates a little to the south in winter from its Arctic 
home in search of food, following the migrations of its prey; some remain in the 
frozen north throughout the year. Its note is said to resemble a loud krau-au 
repeated several times in quick succession, or sometimes it utters a loud rick-rick- 
vick as it rises startled from its perch. 
_ It is difficult to imagine how the Snowy Owl can find subsistence during the 
long. polar winter if it does not leave the frozen tundras where the rivers are all 
iron bound with ice, and no fish can be obtained; where the vast dreary plains 
are covered many feet deep with snow, at the bottom of which the small rodents 
are either engaged in eating the roots of the grasses, or are wrapped in their 
winter’s sleep; when all the wild-fowl have departed, having fled southwards on 
the first signs of the dread winter. Very different is it during the continued day 
of the brief Arctic summer, when the sun never dips below the horizon, all the 
rivers are free, and the surface of the tundras, directly the snows are melted, 
become clothed with a sudden vegetation; then the great flocks of ducks, geese, 
plovers, sand-pipers, and numerous small birds have all returned to their breeding 
quarters, and the Snowy Owl lays its eggs and rears its young with an abundant 
food supply close at hand. 
Among the phenomena of animal life in the far north are the periodical 
migrations of the lemmings; these tiny mouse-like creatures are seized from time 
to time with a mysterious impulse, and collecting in vast hordes start on their 
journey. Crossing rivers the fish take their toll of them as they swim over; 
nothing proves an obstacle to their advance, except the ocean, and fortunate is it 
their line of march does not pass through a cultivated country, or great would be 
the devastation wrought. Animals and birds of all kinds hasten to the feast, even 
the reindeer is said to eat them; the Snowy Owls flocking after them are in this 
manner brought into districts where they are not usually seen, to disappear again 
with the attraction that has allured them. 
Wheelwright states that in Lapland the nest of the Snowy Owl was nothing 
more than a large ball of reindeer moss, placed on the ledge of a bare fell, and 
was jealously guarded by the old birds; he adds that the Laps often kill them 
with a stick when they are robbing the nest. Sometimes the nest is placed on 
the large turf hillocks in some of the mosses. Wheelwright considered the Snowy 
Owl more local than erratic, although, in some years there would appear to be a 
