The Body of a Bird 303 
wondered, when I saw mounted specimens in museums, 
with what special immunity from danger these birds 
were blessed, their beautiful colouring would seem to be 
such a startling advertisement of the bird’s whereabouts. 
But in reality the very diversity in hue is their protec- 
tion, and they merge per- 
fectly into their environ- 
ment of green foliage and 
bright sunlight.” 
Indeed absolute uniform- 
ity of coloration instantly 
reveals the outline of the 
bird entire, and renders it 
very conspicuous. Birds 
which have but few ene- 
mies are often thus mono- 
crome in hue. But look 
at the photographs and 
see how a broken -colora— 9.4. sin Bigen Creeper Grains up thie 
tion baffles the eve. If alae 
the Sooty Tern, Fig. 238, were totally black, it would 
be conspicucus even against a patch of dark-coloured 
mottled shingle. But the transverse lines of white across 
the back totally destroy the symmetry of form, while 
the white wing-edges fairly force the eye to call them, 
not part of a bird sheltering her eggs, but only two among 
a myriad irregular edges of coral rock! 
Observe closely the seven young Flickers clinging to 
their natal stump. As the warriors of Jason sprang forth 
from the ground fully armed, so the very bark, mottled 
