150 The Bird 



night-hawks brush them into rapacious maws, if per- 

 chance they have succeeded in reaching the upper air. 



In tropical forests, where insects are everywhere 

 abundant, the birds seemed to have reaUzed the fact that 

 to each is apportioned certain phases of insect Hfe, and 

 that by hunting in large flocks, instead of competition 

 resulting between birds of different species, they play 

 into each other's hands (or rather beaks). It is of such 

 a flock that Hudson writes: ''The larger creepers ex- 



FiG. 116.— Squid. 



plore the trunks of big trees, others run over the branches 

 and cling to the lesser twigs, so that every tree in their 

 route, from its roots to the topmost foliage, is thoroughly 

 examined, and every spider and caterpillar taken, while 

 the winged insects, driven from their lurking-places, are 

 seized where they settle, or caught flying by the tyrant- 

 birds." 



The Wattled Starlings or Locust-birds of South Africa 

 live in flocks of thousands, and so dependent are they 

 on locusts as food, that their habitat and place of nest- 



