WILD CREATURES OF GARDEN AND HEDGEROW 



birds, for the number destroyed by this one 

 pair must have been enormous, and as the 

 willow wren is a very common bird it must kill 

 millions of harmful grubs in the course of the 

 summer. What a twittering there was from 

 the youngsters each time one of the old birds 

 returned with a beakful of these little cater- 

 pillars, but neither parent ever hurried himself 

 or herself, carefully and deliberately a fair 

 share of the good things was pushed down the 

 throats of certain of the nestlings. As they all 

 appeared equally well-fed and looked after, 

 I suppose the old birds took care that those 

 missed at one visit should be fed first at the 

 next, though how they told one from another, 

 or knew which they had fed last, was a com- 

 plete puzzle to a mere human. The meal 

 over, the little ones would sink back into 

 the nest, while the parent remained for a 

 moment in the entrance hole waiting to 

 see if any of them wanted attention. The 

 nest was kept beautifully clean, everything 

 being carried away by the old birds. They 

 never got soiled when doing this, as the 

 excreta of all nestlings whose parents look 

 after them in this respect is covered with 

 a slimy non-adhesive coating, that enables it 



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