BISET OR ■WILD ROCK-PIGEON. 
147 
and extensive caves, retiring to their inmost recesses, 
and generally beyond the situations selected for ni- 
dification by the auks, gulls, and other aquatic fowl. 
It is also met with upon the northern and western 
coasts of Sutherland, the perforated and cavernous 
rocks which gird the eastern side of Loch Eriholl, 
and those of the limestone district of Durness, fur- 
nishing suitable places of retreat, and again upon the 
eastern coast of Scotland, it is seen about the rocky 
steeps of the Isle of Hass, and the hold promontory 
of St Abb’s Head. 
The supposition of many of our ornithologists 
that this and the preceding species were identical, 
has led to considerable confusion in their writings, 
and produced a mixed sort of description strictly ap- 
plicable to neither. The distinctions, however, be- 
tween the species, even in regard to plumage, are 
such, that, if attended to, no mistake can well arise, 
and if accompanied by a corresponding attention to 
their respective habits, the difference becomes still 
more apparent and convincing. In one we have a 
bird the frequenter and inliabitant of the woods, 
where it roosts, breeds, and perches with security 
and ease upon the trees, like, the ring jiigeon and 
other arboreal species ; in the other, an inhabitant of 
caves and the holes of rocks, and which is never 
known, under any circumstance, to affect the forest 
or perch upon a tree. 
But the rock or wild pigeon is better known to 
our readers as the inhabitant of the pigeon-house, 
