THE MOST MARVELLOUS DRILL IN THE WORLD 



237 



The variety of her positions assumed during the bor- 

 ing process I will not attempt to describe, nor can I, in 

 a brief popular paper, enter upon the very strange mus- 

 cular and anatomical action which accompanies the proc- 

 ess. But I have shown my ichneumon as she appeared 

 after the drilling was well under way ; the large disk at 

 the extremity of the body being a contractile tissue dis- 

 tended by the loop of the drill within, and by which 

 the pressure is communicated to the straight shaft be- 

 low. By a muscular wriggling motion, continued with 

 patience for hours sometimes, the horse-hair gimlet 

 has sunk three inches into the wood, bringing up to 

 the surface a continual pouring of fine sawdust. 

 The membranous disk has disappeared by gradual 

 contraction, and the body at length assumed the 

 position which we now see in our dead specimen 

 on the tree, with the two loops of the sheath- 

 ing parts separated and meeting around the 

 drill where it enters the wood below, this 

 short section of about half an inch beneath 

 the tip of the body being all that is now 

 to be seen of the original four-inch bore. 

 But this last effort was evidently too 

 much for the insect. It exhausted her 

 strength, and she died without being 

 able to withdraw the shaft. 



And what is it all about ? What 

 fun can there be in such laborious 

 work, and in such hot August 

 weather too ? The intention of 

 this ichneumon is no less aston- 

 ishing than her mechanical 

 skill. She knows very well 



