60
THE INTER-RELATIONS OF
well known, some northern birds are wanting in the southern counties,
while there are characteristic or abundant eastern counties and western
counties species. This geographical or topographical distribution may
to some extent be due to difference of vegetation, but it is evidently
chiefly influenced by meteorological conditions.
Perhaps the Nightingale is the most famous of the fastidious birds
that visit England, since its sweet nocturnal notes make it well known
where it visits, and also make it missed where it does not. The
Nightingale does not appear to migrate so far west as Devonshire and
Cornwall, nor so far north as our northern counties, except to a small
district in the neighbourhood of Doncaster in the south-east of
Yorkshire, while it is absent from both North Wales and Ireland.
But curiously enough though not in Scotland, the Nightingale does
not altogether absent itself from Sweden. Its evident fondness for
the sunny south seems to be contradicted by its peculiarity of warb-
ling in the silent sunless night. Milton says :—
" Sweet bird that shunn'st the noise of folly,
Most musical, most melancholy,
In her saddest, sweetest plight,
Smoothing the rugged brow of night,
While Cynthia checks her dragon yoke
Gently o'er the accustom'd oak."
Again some birds love the cold, as the Eider Duck, and the
Chatterer, which latter breeds within the Arctic Circle and comes not
farther south in England than Northumberland ; and some well-
known birds that are not driven away by the winter's cold change
their appearance or their habits when rigorous weather whitens the
land with snow. The Lapland Bunting though tawny in summer
is white and black in winter. Almost domesticated by the necessity
for food, the Robin Red-breast will leave the hedgerows and come
to the doorstep, and the Lark will no longer warble solitarily in
the sky, but in great flocks will become an easy prey to those who
go forth to the fields with nets and guns.
Reptiles are very sensitive to climatic conditions and abound only
in hot climates. Serpents have a restricted range, while Alligators and
Crocodiles are confined to the rivers of tropical regions. Even
marine reptiles, such as the Turtle, are found only in the warm seas of
the globe, though as we know from the chelonian remains of the
London Clay of the Isle of Sheppey they were once abundant in the
seas where is now the dry land of the county of Essex, an area