The Glow-Worm 



quickly shut by the inmate's mere withdrawal 

 into his house and as easily opened when the 

 hermit goes forth. With this system of 

 closing, the abode becomes inviolable; and 

 the Drilus knows it. 



Fixed to the surface of the shell by an 

 adhesive apparatus whereof the Lampyris 

 will presently show us the equivalent, he re- 

 mains on the look-out, waiting, if necessary, 

 for whole days at a time. At last, the need 

 of air and food oblige the besieged non- 

 combatant to show himself; at least, the door 

 is set slightly ajar. That is enough. The 

 Drilus is on the spot and strikes his blow. 

 The door can no longer be closed and the 

 assailant is henceforth master of the fortress. 

 Our first impression is that the muscle moving 

 the lid has been cut with a quick-acting pair 

 of shears. This idea must be dismissed. 

 The Drilus is not well enough equipped with 

 jaws to gnaw through a fleshy mass so 

 promptly. The operation has to succeed at 

 once, at the first touch: if not, the animal 

 attacked would retreat, still in full vigour, 

 and the siege must be recommenced, as ardu- 

 ous as ever, exposing the insect to fasts in- 

 definitely prolonged. Although I have never 

 come across the Drilus, who is a stranger to 

 my district, I conjecture a method of attack 

 9 



