SEPTEMBER. 153 



tumbling upon a fly in the middle of its dinner. But 

 the flies are so nimble that, although there may seem 

 to be two or three of them on every blossom, you 

 may watch a wasp knocking its head against a score 

 of flowers without once finding a fly at home. Yet 

 the manner of the flies' escape at the same instant 

 that the headlong wasp arrives is too quick for human 

 eyesight. 



A CATERPILLAR'S WILES. 



This swift conflict of wits and agility between 

 eater and eaten, with the odds on the escape of the 

 latter, runs through all nature. The hawk hunts far 

 and wide, and stoops many times before she strikes 

 her quarry ; and the heron sees and is seen by scores 

 of fish ere he plunges with success at one. But the 

 wasp belongs to a very high class of hunters, for it 

 has the instinctive intelligence to adapt its methods 

 to the prey pursued. When, for instance, he searches 

 for small caterpillars, there is no promiscuous bluster 

 in his tactics. Caterpillars do not sit on every leaf, 

 like flies on every blossom ; and wasp grubs would 

 die hungry if their providers went about banging their 

 heads against all the leaves in a hedge. So now the 

 wasp hovers cunningly up and down one twig after 

 another, looking, or more probably smelling with its 

 "antennae," or feelers, for its prey. When it finds a 

 curled-up leaf, it quickly ascertains, by hurrying 

 quickly from the front door to the back, whether 

 the fat little caterpillar is at home; and, if so, it 

 deliberately sets to work to cut, or, rather, bite, its 

 way in. But the caterpillar is prepared for this, and 



