310 ZOOLOGY. 
loose plumage is also quite characteristic, but is not peculiar, being occa- 
sionally met with in the Caprimulgide (night-hawks). 
The brain is more voluminous than in other rapacious birds, and is 
protected by a remarkably thick, cellular cranium, which contributes to the 
great size of the head, as apparent in the living bird. The organ of 
hearing is very large and possesses much quickness and delicacy, and a 
peculiar formation of the eye gives the owls a power of sight of the most 
exquisite character. It is so constructed that the small amount of light at 
twilight, or even in the night, is sufficient to produce perfect vision, though 
the full daylight is too strong and dazzling for most of the species. 
The flight of the owls 1s less eal and less capable of being eS, 
continued than that of the preceding families. It is produced by repeated © 
flappings and has the advantage of being entirely without noise, owing to 
the peculiar general structure of the wings, and a fine hair-like web on 
the outer edge of the first quill. They are thus enabled to steal upon 
their prey unawares and under cover of the darkness of night. 
Their plumage is almost invariably of dull and uniform colors, and is in 
a great measure free from the diversity characteristic of age and sex in the 
Falconide. Being nocturnal strictly, or active only in the twilight of the 
evening or the morning, is generally characteristic of this class ; a few species, 
however, are diurnal, and pursue their prey or attend to the wants of their 
young in the full glare of daylight. Of these the great snowy owl (NVyctea 
nivea) and the hawk owl (Surnia ulula), both found in the northern parts 
of America, are examples. These are exceptions only, much the greater 
number of species being of the former character. 
The owls rarely devour any animals which have not recently suffered 
death, though they are not always contented with being themselves the 
instruments of destruction ; some species instinctively follow the hunter in 
the northern countries, and pick up with eagerness grouse and other birds 
recently killed by his gun. Their period of activity being in the night, 
their repose is necessarily during the day, and if then disturbed most of the 
species make gestures of a very ludicrous character, which seem chiefly 
intended, however, to enable them to get a fair view of the intruder. 
Some species fly off immediately upon perceiving that they are discovered. 
“Some owls tear their food like the falcons, but the greater number 
swallow small quadrupeds, birds, and insects entire, subsequently ejecting 
from the mouth the hair, bones, and other indigestible matter rolled into 
pellets by a peculiar action of the stomach. Their food is entirely animal, 
and embraces every living thing which can be conquered by force or 
stealth. 
The nesting-places of the owls are usually in hollow trees, fissures, or 
eaverns in rocks, dilapidated buildings, or similar places. They also 
frequent such localities habitually during the day, or sometimes the 
proteetion of a pine tree serves them when belated in the morning. This 
peculiar family has been regarded with feelings nearly akin to superstition 
fromthe earliest ages. The grotesque and oddly-shaped forms of most of 
the species, their preference for the darkness of night or the gloomiest 
514 
