304 BRITAIN^S BIRDS AND THEIR NESTS. 



The nest is a cup of reed-flags and flat grasses, lined 

 with reed-flowers, and placed among the sedge or reeds 

 close to the water. The five to seven eggs are very 

 glossy ; they have a few reddish - brown streaks on a 

 creamy ground, the whole effect being very delicate. 

 Two females sometimes lay together in one nest, and a 

 single pair produces two broods in a season. 



The nestlings are of the usual Passerine type, but . 

 we may mention one special feature. Inside the mouth 

 are four conspicuous whitish spots. Similar markings 

 of various patterns and coloui's are found on the 

 tongue and other parts of the mouth of many Passerine 

 nestlings. Attention has only recently been given to the 

 point, and it has not yet been fully studied. We know, 

 however, that such markings tend to occur in those 

 species whose nests are in deep shade ; in a thick reed- 

 bed, for instance, as in the present case. This is strong 

 evidence in favour of the theory that the markings are 

 guides for the parents at feeding-time. In a photograph 

 of a Bearded-Tifs nest, with six young ones gaping for 

 food, six groups of white spots stand out from the 

 surrounding darkness. 



Family, CINCLID^ (Dippers). 



THE DIPPER, OR WATER=-OUSEL 



(Cinclus aquaticus). 



Plate 111. 



Any one who knows the Highland 'burns,' running 

 swiftly over their rock-strewn beds, must know the 

 Dipper, a little, rather 'dumpy' bird, with a conspicuous 

 white breast and an otherwise dark plumage. Usually 



