The Hunting Wasps 



delicate. Later, getting bigger and bigger 

 in time, will come the larger joints of veni- 

 son. 



The burrow must be kept shut during the 

 mother's absence, to save the larva from re- 

 grettable intrusions; nevertheless the en- 

 trance must be one that can be opened very 

 frequently and hurriedly, without much dif- 

 ficulty, when the Wasp returns laden with her 

 prey and watched by the sharp eyes of daring 

 parasites. These conditions could not be 

 obtained with a compact soil such as that in 

 which the Digger-wasps usually make their 

 abodes: the door, left to itself, would stay 

 open; and so, each time, there would be the 

 long and toilsome job of either blocking up 

 the entrance with earth and gravel or un- 

 blocking it, as the case might be. The house 

 therefore must be dug in ground with a very 

 loose surface, in fine dry sand, which will at 

 once yield to the slightest effort on the 

 mother's part and, as it slides down, will 

 close the door of its own accord, like a curtain 

 which, when you thrust it aside with your 

 hand, lets you pass through and then falls 

 back again. There you have the series of 

 actions as deduced by man's reason and as 

 practised by the Wasp's sagacity. 

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