142 
O WLS. 
of owls that collected from all sides to prey on the hosts of these rodents which 
recently infested portions of Scotland. In all owls the indigestible remnants of 
their food, such as bones, feathers, hair, scales, etc., are formed into pellets in the 
stomach, and disgorged; such castings affording incontestible evidence of the nature 
of the food of these birds. All owls are furnished with a syrinx, or organ of voice, 
which most of them know only too well how to use ; their cries taking the form 
of hooting, howling, screeching, or a weird kind of laughter. It is from these 
cries that the names of these birds are derived in many languages, as witness the 
English owl, the German eide, the Latin ulida, and the Hindustani ulu. 
Barn-Owls. 
Family SlRIGID^J. 
Although one of the commonest and most familiar of all the group, the barn- 
owl (Strix Jlammea ) is of special interest as constituting, together with a few 
nearly-allied forms, a family apart from that which includes all the other repre¬ 
sentatives of the order. This family (Strigidce) is characterised by the breast-bone, 
or sternum, having its lower margin entire, and also by its keel being firmly united 
with the furcula. Then, again, the third claw has its inner margin serrated, while 
the second and third toes are of equal length. An additional peculiarity is to be 
found in the presence of a small patch of stiff feathers between the adjacent portions 
of the face-discs. In the cannon-bone the bridge over the hollow at the upper end 
is absent. As a genus, the barn-owls are characterised by the completeness of the 
discs round the eyes, which are large, and narrow rapidly as they approach the 
beak. The wings are long, and extend considerably beyond the tail; the beak is 
straight at the base, and decurved only at the tip; and the aperture of the ear is 
large, and furnished with a distinct lid. The head is devoid of tufts, and the rather 
long legs are feathered down to the origin of the toes. 
The common barn-owl has a wider distribution than any other member of the 
order, being in fact almost cosmopolitan, although comparatively rare in the extreme 
north, and unknown in New Zealand, parts of Oceania, Persia, Japan, and China. 
With this extensive distribution, it would be only natural to expect great variation 
in the colour of the plumage; and, as a matter of fact, we find representatives of 
this owl from widely distant regions so unlike one another that it is at first sight 
difficult to believe that they belong to the same species, more especially as there 
are also differences in point of size. In the ordinary British form, of which the 
length averages 14 inches, the face-discs are white, with their margins defined by 
the feathers being tipped with brown; the top of the head and neck are pale buff, 
dotted with specks of black and white; on the back and wings a darker buff, 
speckled with grey and irregularly mottled with black-and-white, obtains; the 
tail-feathers are pale buff above, marked with five transverse grey bands; and the 
whole of the under-parts are white. From this normal coloration there is every 
intermediate stage to one where the eye-discs are rusty red, the under-parts tawny, 
and the back darker than usual; while in other cases the discs may be grey, and 
the whole plumage tending more or less to this tinge. In other instances, however, 
