The Life of the Weevil 
self her way out of the pea, which is now 
quite hard. The larva knows of this future 
helplessness and provides against it with 
consummate art. With its strong jaws it 
bores an exit-shaft, absolutely circular, with 
very clean-cut sides. Our best ivory-carvers 
could produce nothing neater. 
To prepare the door of escape in advance 
is not enough; we must also think of the 
tranquillity essential to the delicate work of 
the nymphosis. An intruder might enter 
through the open door and work mischief 
upon the defenceless nymph. This opening 
must therefore be kept shut. And how? 
Here is the device. 
The grub boring the exit-hole eats the 
floury matter without leaving a single crumb. 
On reaching the skin of the seed, suddenly 
it stops short. This semitranslucent mem- 
brane is the screen protecting the chamber in 
which the metamorphosis takes place, the 
door that defends the cabin against ill-inten- 
tioned intruders. Jt is also the only obstacle 
which the adult will encounter at the time 
of moving. To lessen the difficulty of forc- 
ing it out, the grub takes the precaution of 
carving a groove of least resistance inside the 
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