THE REED WARBLER 55 



become very anxious and garrulous when their nest is 

 menaced by danger, and flit from reed to reed, or twig to twig, 

 uttering a series of harsh scolding cries, which sound very 

 like those used by the Whitethroat on similar occasions. The 

 nests are often built and left for several days before the first 

 fdgg is laid — a peculiarity which I have often remarked in the 

 Song Thrush and the Chaffinch. 



The eggs of the Eeed Warbler are four or five in number, 

 very pale blue in ground colour, spotted and blotched with 

 greenish-brown, and paler markings of violet-gray. Some 

 eggs are slightly streaked with very dark brown, and on 

 some the spots are large and confluent, on others small and 

 evenly dispersed over most of the surface. It is worthy of 

 remark how very distinct the eggs of the British AYarblers 

 are. In each group the eggs almost without exception are 

 peculiar. Thus in the Willow Warblers we have pure white 

 eggs spotted with reddish-brown ; in the Tree Warblers the 

 eggs are s?Jmon-pink, spotted with purplish-brown ; in the 

 Grasshopper Warblers the finely powdered brown markings 

 and their general pinky appearance are characteristic of them 

 alone ; whilst in the Eeed Warblers greens and olive-browns 

 are the predominant colours. In the true Warblers — as, for 

 instance, the Blackcap and the Whitethroats — there is not 

 quite so much uniformity, probably because the species in 

 this group are comparatively of much greater antiquity than 

 those in the preceding ones. It seems to me that the very 

 distinct variations in the eggs of this latter group show 

 a wide degree of differentiation of many of the species ; but 

 in the allied groups, although the species have become 

 fairly defined, the eggs have not yet had time to vary, 

 and consequently a certain type of ^gg runs through each 

 respective group. What part these variations play in the 

 economy of the birds still remains to be discovered ; but 

 I think it is very clear that these well-marked types of 



