XIV 
INTRODUCTION. 
also formed according to the taste of the owner, and is as often 
found without any lining at all, as it is thickly lined with 
feathers. 
There are many instances in which circumstances have led 
to a deviation from the usual habit. Those Eagles and Hooded 
Crows inhabiting the Shetland Islands, which would build their 
nests of sticks, were such materials to be had, are there com¬ 
pelled to substitute the larger species of sea-weed. A Carrion 
Crow which resorted to the Fern Islands to breed, for the same 
reason (the absence of sticks), made its nest in a hole in the 
ground, surrounding it, to give it sufficient depth, with a wall 
of sods. 
There are a few deviations from the usual instinct, which, 
not being influenced by local causes, are very remarkable; 
and in no instance which has come under my notice, more so 
than in the nest of a Blackbird, sent me by my friend, the 
Rev. W. D. Fox, which is lined with black hair, instead of 
the usual material, dry grass ; the same circumstance having 
occurred several years in succession. 
With regard to the situation of their nests, birds seem to be 
left much more to the influence of their own choice, construct¬ 
ing them with surprising skill, in places apparently most un¬ 
suitable. Some species, leaving their natural mode of life, and 
their own wild haunts, have adapted their habits to our own, 
and being to a certain extent domesticated, have become our 
confiding friends and delightful companions. The Swift, the 
Martin, and the Swallow, once the inhabitants of the inland 
rocks and lonely sea cliffs of our coast, have now become the 
voluntary inmates of our dwellings, cheering us with their 
cheerful notes and elegant evolutions. The shy Hawk, the wily 
Raven, and the midnight Owl, leaving their native woods, have 
built their nests in the towers and steeples of our towns and 
cities. The Magpies, too, which with us are so suspicious of 
wrong, build their nests under the eaves of the Norwegian cot¬ 
tages. Numerous instances might be given, in which birds 
have chosen the most strange and singular situations for their 
