EGGS OF BRITISH BIRDS. 183 



THE COMMON DIPPER. 



(ductus aquaticus.) 

 Plate 51, Fig. 8. 



The distribution of the Dipper in Great Britain is chiefly 

 confined to the mountainous districts of the west and north of 

 England, including Wales, and throughout Scotland, extending 

 to the outer Hebrides and the Orkneys, but not to the Shetland 

 Isles. In Ireland it is found in similar localities to those in 

 Britain. The Dipper in a more or less modified form appears 

 to occur throughout the Palrearctic region and the Himalayas 

 wherever rocky mountain-streams are to be found. 



By the first week in April, should the weather be at all favour- 

 able, the birds are engaged in nest-building. The site for the nest 

 is usually amongst the rocks, never in a tree or bush, although 

 occasionally amongst their gnarled and moss-grown roots. In 

 form it is somewhat like the Wren's, domed; but the hole which 

 admits the parent birds is very low down the side, and can seldom 

 be seen unless from below, the entrance overhanging a little. 

 Inside this mossy dome a nest of the ordinary open style is con- 

 structed, apparently quite distinct from it, without being in any 

 way woven into it. 



The eggs of the Dipper are four or five in number, and can 

 never be confounded with the eggs of the Thrushes, except in 

 size and form. They are pure white and spotless, somewhat less 

 than a Song Thrush's egg in size. The shell, however, does not 

 possess that beautiful gloss so characteristic of the eggs of the 

 Kingfisher and the Woodpecker, and is somewhat rough in texture. 

 They vary in length from 1*1 to 0*95 inch, and in breadth from 

 0-77 to 0-7 inch. 



The Black-bellied Dipper (Cinclus melanog aster) of Scandinavia, 

 has occurred on the eastern coasts of England. Its eggs resemble 

 those of C. aquaticus. 



THE EOBIN. 

 (Erithacus nubecula.) 



Plate 51, Figs. 2, 3. 



Throughout Great Britain and Ireland the Robin is everywhere 

 a well-known bird in those localities where there is sufficient 

 cover ; like the Sparrow, it is a close attendant on cultivation 



