pectively for their nests. "The
common sandpipers' eggs assimilate so closely with the tints around them
as to make their discovery a matter of no small difficulty, as every
oologist can testify who has searched for them. The pewits' eggs, dark
in ground colour and boldly marked, are in strict harmony with the sober
tints of moor and fallow, and on this circumstance alone their
concealment and safety depend. The divers' eggs furnish another example
of protective colour; they are generally laid close to the water's edge,
amongst drift and shingle, where their dark tints and black spots
conceal them by harmonising closely with surrounding objects. The snipes
and the great army of sandpipers furnish innumerable instances of
protectively coloured eggs. In all the instances given the sitting-bird
invariably leaves the eggs uncovered when it quits them, and
consequently their safety depends solely on the colours which adorn
them."[81] The wonderful range of colour and marking in the eggs of the
guillemot may be imputed to the inaccessible rocks on which it breeds,
giving it complete protection from enemies. Thus the pale or bluish
ground colour of the eggs of its allies, the auks and puffins, has
become intensified and blotched and spotted in the most marvellous
variety of patterns, owing to there being no selective agency to prevent
individual variation having full sway.

The common black coot (Fulica atra) has eggs which are coloured in a
specially protective manner. Dr. William Marshall writes, that it only
breeds in certain localities where a large water reed (Phragmites
arundinacea) abounds. The eggs of the coot are stained and spotted with
black on a yellowish-gray ground, and the dead leaves of the reed are of
the same colour, and are stained black by small parasitic fungi of the
Uredo family; and these leaves form the bed on which the eggs are laid.
The eggs and the leaves agree so closely in colour and markings that it
is a difficult thing to distinguish the eggs at any distance. It is to
be noted that the coot never covers up its eggs, as its ally the
moor-hen usually does.

The beautiful blue or greenish eggs of the hedge-sparrow, the
song-thrush, and sometimes those of the blackbird, seem at first sight
especially calculated to attract attention, but it is very doubtful
whether they are really so conspicuous when seen at a little distance
among their usual surroundings. For the nests of these birds are either
in