ABUNDANCE OF CATERPILLARS 101 



long-tailed tits ; these will not sit still and wait like the 

 others, but all, a dozen or fifteen to a brood, hurry after 

 their busy parents, all the time sending out those 

 needles of sound in showers. Of hard-billed birds the 

 chaffinch, as usual, was the most numerous, but there 

 were, to my surprise, many yellowhammers ; all these, 

 like the rest, with their newly brought out young. The 

 presence of the hawfinch was another surprise ; and 

 here I noticed that the hunger call of the young 

 hawfinch is the loudest of all a measured, powerful, 

 metallic chirp, heard high above the shrill hubbub. 



Watching one of these busy companies of small birds 

 at work one is amazed at the thought of the abundance 

 of larval insect life in these oak woods. The cater- 

 pillars must be devoured in tens of thousands every 

 day for some weeks, yet when the time comes one is 

 amazed again at the numbers that have survived to 

 know a winged life. On July evenings with the low 

 sun shining on the green oaks at this place I have seen 

 the trees covered as with a pale silvery mist a mist 

 composed of myriads of small white and pale-grey 

 moths fluttering about the oak foliage. Yet it is pro- 

 bable that all the birds eat is but a small fraction of 

 the entire number destroyed. The rapacious insects 

 are in myriads too, and are most of them at war with 

 the soft-bodied caterpillars. The earth under the bed 

 of dead leaves is full of them, and the surface is hunted 

 over all day by the wood or horse ants Formica rufa. 

 One day, standing still to watch a number of these ants 



