HAWKS AND OWLS. 38 
It is sometimes thought that shrews, although 
killed by the barn-owl, are invariably refused by the 
bird as food; and it has even been suggested that 
the owl confounds them with true mice, and slaughters 
them by mistake. Such, however, is not the case, 
for a careful examination of the pellets rejected by 
the bird proves the contrary beyond possibility of dis- 
pute. Dr. Altam, a German naturalist, showed this 
fo be the case as long ago as the year 1862, 
when he published the result of an examination 
of seven hundred and six pellets of the barn-owl. 
The principal remains found in these consisted of 
sixteen bats, three rats, two hundred and thirty- 
seven mice, six hundred and ninety-three field-mice, 
jifteen hundred and ninety shrews, and twenty- 
two birds—incontrovertible evidence that the owl 
is not too dainty to devour the shrews which it 
captures. 
Now and then the barn-owl varies its diet with fish, 
eels, large insects, &c., the latter consisting princi- 
pally of the various ground-beetles which stir abroad 
only after darkness has fairly set in. The won- 
derfully keen vision of the owl, however, enables 
it to detect a far smaller object than many a 
ground - beetle; its eyes, indeed, seeming to be 
almost as sharp by night as are those of the kestrel 
by day. 
It is commonly thought that the bird owes its 
singular powers of vision to the large feathery discs 
which surround the eyes, and which are supposed to 
concentrate the rays of light upon them. Waterton, 
D 2 
