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 limited extent various species of 

 Buho, 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 

 is more direct, and in Surnia uliola 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 Sceloglcmx — 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 

 grouse, and so forth, Xinox connivens being 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 Ketivpa. 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, muffled 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 



