EGGS’ OF THE BIRDS: DESCRIBED 
Birds’ eggs often vary, some considerably, in the colour, shades, 
shape, size and distribution of the markings, and sometimes 
even in the outline of the shell. 
The average period of incu- 
bation is about two to three weeks. 
COLOURS OF PLATE LIX. 
WILLOW WREN 
Pure white, spotted red- 
dish-brown (shell very 
thin) 
CHAFFINCH 
Pale bluish or bluish-green, 
streaked and blotched dull 
purple (most at larger 
end) 
House MARTIN 
Pure white (no markings) 
RoBIN 
Pale ~reddish-white, with 
darker red blotches and 
spots 
REED WARBLER 
Greenish-white, blotched 
and freckled ashy-grey 
WHITETHROAT 
Dull greenish-white,speck- 
led olive-grey or green- 
ish-grey 
SAND MARTIN 
HEDGE SPARROW 
Pure greenish-blue (glossy) 
SWALLOW 
White, spotted purplish- 
red (variable) 
SwIFtT 
Pure white (no markings), 
shell vough (shape a 
long oval) Pure white (no markings, 
BULLFINCH shell thin) 
Greenish-blue, spotted and SpoTTeD FLYCATCHER. 
streaked dark purple Pale greenish-white or 
(most at larger end) bluish-white, blotched 
and clouded reddish- 
brown (faded blood-red) 
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