THE BIRD-LIFE OF LONDON 
floating or swimming to and fro far away from the banks 
near the centre of the pool. As if conscious of its safety, 
it may be seen picking insects from ‘the water or from 
the stems of the aquatic plants, and at intervals diving 
beneath the surface. It might almost be said to fly to 
and fro through the water, so deft are its movements. 
If a pair of Grebes are in company one only dives as a 
rule, the other remaining on the surface as if on the 
look-out ; but sometimes both disappear together, and 
indulge in aquatic gambols, chasing each other hither 
and thither in sportive play. During the nesting season 
the female may be noticed diving again and again and 
bringing bunches of weed from the bottom to add to her 
nest. ‘lhe male sometimes joins her in her dive, but 
seldom brings up any material. The food of this Grebe 
consists of small fishes, aquatic insects, frogs, molluscs, 
seeds, and tender buds and shoots of plants. Its note is a 
shrill kzk or kek, and during the breeding season both birds 
utter a harsh, grunting cry. It breeds in April, May, and 
June, and probably pairs for life, nesting regularly in the 
same spots. It is toa great extent gregarious even during 
summer, and in places where it is at all common numbers 
of nests are built in one vicinity. ‘The big nest, composed 
of decaying aquatic vegetation, with a shallow cavity at 
the top, lined wth similar but finer material, is as often as 
not a floating raft moored to the flags and reeds. Other 
nests have their foundation at the bottom of shallower 
water. ‘hey are added to at intervals to resist the in- 
roads of the lapping waves. ‘The three to five eggs are 
white and chalky, but the interior of the shell is green, 
and very elliptical in form. When disturbed the sitting 
bird is careful to cover her eggs with bits of wet weed 
before leaving them. ‘The young chicks are equally at 
home in the water. 
The adult male Great-crested Grebe has the general 
colour of the upper parts below the neck greyish brown, 
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