MINERS 39 



Another genus of these " fossorial wasps " is 

 Tachytes, which resembles Sphex in its habits. 

 It sinks vertical shafts in the ground, and uses 

 insects of the order Orthoptera for the stocking of 

 its pantries. Some species take field crickets, some 

 grasshoppers, others mole crickets ; and one has 

 the courage and skill to use the murderous mantis, 

 whose scissor-like fore legs could easily cut Tachytes 

 into little bits. But Tachytes appears to know its 

 risk and relies on strategy : it flies around the 

 mantis for a time, just out of reach, and the rapid 

 turning of the latter's head to enable it to keep 

 at least one eye on Tachytes produces confusion 

 in its nerve-centres. Then is Tachytes'' chance : it 

 swoops down and thrusts its sting between the 

 bases of the formidable fore legs, paralyzing the 

 nerves that operate them. The other legs are 

 served in like fashion, and the mantis is at once 

 in a condition to be hauled off to Tachytes' 

 larder. 



In another genus of small mining wasps — Astata 

 — a strange taste is exhibited — judged from the 

 human standpoint we should have to call it a 

 depraved taste. These wasps for the sustenance 

 of their progeny select two of the most repulsive 

 of insects — one, a plant-bug {Pentatoma), the other 

 a small cockroach. Nearly all the bugs are pro- 

 vided with stink-glands which emit the most 

 disgusting odour, and Pentatoma is not one of the 

 exceptional kinds. Some people say, however, that 

 the smell given off by the cockroach is even worse 



