VI STRIGIDAE 401 
than Falcons or Eagles. In the perpetual day of the Arctic summer 
the Snowy Owl and the Hawk-Owl (Surnia ulula) cannot of 
course be nocturnal, while to a lmited extent various species of 
Bubo, Scops, Ninox, Glaucidium, Carine, Nyctala, and Asio may be 
seen abroad in the hours of light; so that in many cases sight 
may aid in the capture of prey as much as hearing. 
The noiseless flight is buoyant, but usually slow and some- 
what wavering, with frequent beats of the wing; occasionally it 
ow 
is more direct, and in Surnia ulula almost Hawk-like. Owls 
apparently prefer to perch with the first and fourth toes behind, 
and on a level surface to stand with three toes in front; their gait 
on the ground is awkward,and being arboreal birds—with the excep- 
tion of Speotyto and Sceloglaux—they rarely walk to any extent. 
The food consists of small mammals, such as lemmings, rats, voles, 
and mice; of insects, with perhaps beetles in especial; and to a 
less degree of birds, reptiles, bats, worms, slugs, and snails. The 
stronger forms even capture young fawns, rabbits, hares, large 
erouse, and so forth, Minox connivens bemg a great enemy of the 
young of the Koala (an Australian marsupial); while the Snowy, 
Mottled, Screech-, and Wood-Owls occasionally take fish, which, 
with crabs, constitutes the chief diet of Aetupa. The manner of 
procuring sustenance varies with the object sought. Insects are 
frequently caught upon the wing, but ordinarily the ground is 
quartered after the manner of Harriers, and a pounce made upon 
the prey, which is secured in the long curved talons. The smaller 
creatures are swallowed entire or carried in the bill; the bigger 
are conveyed, hanging between the feet, to some convenient spot, 
where they are torn to pieces and sometimes plucked. Bones, 
fur, feathers, beetles’ elytra, and the like are ejected as round or 
cylindrical pellets, which commonly lie thickly around the nests or 
feeding-places, and clearly shew the nature of the food. 
The note varies from a loud hoot to a low, muftled sound or a 
clear, musical cry; the utterance of both young and adults being 
in some cases a cat-like mew, while the Screech-Owl snores when 
stationary. The “hoot” is said to be produced by closing the 
bill, puffing out the throat, and then liberating the air, a pro- 
ceeding comparable to that of the Bitterns (p. 88). On the 
whole the voice is mournful and monotonous, but occasionally it 
resembles a shrill laugh. If a nest be made, it is commonly 
placed in a hole in a tree or on a ledge of rock, but many species 
VOL. IX 2D 
