go BRITISH BIRDS, WITH THEIR NESTS AND EGGs. 
a brick-earth cutting at Kemsley, near Sheppy. Nidification lasts from May to 
August, nests being most abundant in the latter half of May. 
The nest is usually bag-shaped, consisting of a mere thick lining to the hole 
in which it is situated; the top being widely open, so that the light generally 
falls directly upon the eggs; the materials are similar to those used by the 
Common Sparrow—straw, hay, and a mass of poultry-feathers. The eggs number 
from four to six; they are rather smaller than those of the House-Sparrow, and 
vary nearly as much (perhaps quite as much, if one could obtain a sufficient series 
to decide the point); I have taken them greenish-white, with scarcely perceptible 
grey speckling; greenish-white, speckled with grey, spotted with two shades of 
sepia, sometimes with the heaviest markings in a subterminal zone; somewhat 
greyer, mottled and streaked with grey (not unlike an egg of the Pied Wagtail) ; 
greyish-white, thickly mottled and blotched with grey, most densely at the larger 
end, also with one or two blackish dots (not unlike a Titlark’s egg); dull white, 
heavily blotched and streaked with vandyke-brown in two shades, and with small 
grey shell-spots; similar, but so densely streaked and splashed with brown as 
almost to hide the ground-colour; lastly rufous-brown, speckled and streaked, 
especially at the larger end, with darker brown (resembling a reddish variety of 
the Tree-Pipit). The darker and more ruddy eggs are most characteristic of the 
species; but most of those which I obtained from Kentish nests were of the lighter 
varieties, though the eggs in one clutch sometimes exhibit considerable modification 
in this respect. It is possible that the colouring of the eggs may have a local 
significance, inasmuch as Lord Lilford’s experience in Northamptonshire led him 
to the conclusion that the ground-colour, as a rule, was lighter than in eggs of 
the House-Sparrow; whilst those which I obtained in Norfolk were usually remark- 
able for their darker ground-tint, although exceptions did occur. 
It seems to me more probable that light in some way affects the colouring of 
eggs; inasmuch as, not only are most eggs which are laid in the dark pure white, 
but all those which I have found in heavily shaded positions have been pale and 
little marked, in comparison with those exposed to direct daylight; the lightest 
eggs of the Tree-Sparrow which I obtained in Norfolk were those taken from the 
horizontal branch of a willow, where the light only entered imperfectly over one 
side of the nest-cavity; those in the top of the stump, which were fully exposed 
to the sky, were deepest in colouring; the nest containing an almost white egg 
was from the ruined lime-kiln, and was almost as much in the dark as if it had 
been taken from a Sand-Martin’s burrow. Lord Lilford’s eggs being taken from 
holes in full-sized trees, and not from the tops of pollards, were probably but little 
exposed to light. 
