98 BRITISH BIRDS, WITH THEIR NESTS AND EGGS. 



to make me suspect its existence ; I marked the spot by treading a flint into the 

 edge of the path, and a week later again visited the spot, when finding that it 

 contained four eggs, I took it at once rather than risk the chance of its discovery 

 by someone else. 



Lord Lilford's experience of the Chiffchaff's nest in Northamptonshire differs 

 somewhat from my Kentish experience of it ; he says that it "is hardly to be 

 distinguished from that of the Willow- Wren, but is, I think, more often placed 

 at some height from the ground than is the case with that bird." 



Judging from the nests which I have robbed, as well as those which I have 

 preserved, I should say that the majority of those of the Chiffchaff were slightly 

 higher in proportion to their width and more contracted round the opening than 

 those of the Willow- Wren ; the outside also is perhaps more generally decked with 

 dead leaves in nests of the former than of the latter species ; but to be sure of 

 one's facts, one ought to be able to compare a large number of nests from different 

 counties. 



The nest of the Chiffchaff is cave-like, or semi- domed, with a tolerably wide 

 opening ; the thickest portion of the structure is at the top, probably with a view 

 to protection against rain ; the walls are formed of coarse dead grass-stems inter- 

 twined with dead blades of grass, plant-fibre, rootlets, dead as well as skeleton- 

 leaves and spiders' cocoons ; the inside is lined with fine rootlets, horsehair and a 

 number of feathers carefully smoothed down. The number of eggs varies from 

 five to seven, the former being the usual number ; in colour they are pure white, 

 though when not blown the yolk gives them a pink tinge ; * they are more or 

 less dotted or spotted, as a rule, with deep chocolate or pitchy markings ; but some- 

 times these spots are mixed with other larger ones of a sienna red colour, with 

 here and there a pale lavender shell spot. Sometimes the spots are chiefly 

 confined to the larger end, sometimes they form an unequal, oblique, and somewhat 

 vague belt across the surface, often they are evenly scattered over the entire egg ; 

 but in spite of all these little modifications there is never the slightest difficulty 

 in recognizing, at a glance, the egg of the Chiffchaff, it is as characteristic as 

 that of the Lesser Whitethroat. 



The food of this species consists of many kinds of small insects, their larvae, 

 and of spiders : it also feeds on elderberries and currants as soon as these are 

 ripe : it seeks its insect food chiefly in the trees, but does not scorn to snatch a 

 small beetle or spider from the ground, or to chase a gnat or fly in the air. Its 

 flight is very undulating and not specially rapid. 



* Eggs which have been parti}- incubated lose their purity of colouring, becoming somewhat creamy ; but 

 this is not a peculiarity of the Chiffchaff alone ; therefore to describe the egg as cream-coloured is not strictly 

 correct. 



