How is it then that the acridian trusts to a hold so easily broken?
The talons of the skin hold firmly so long as the labour of escape continues, although one would expect it to shake the firmest grip; yet they yield at the slightest shock when the labour is terminated.

There is evidently a condition of highly unstable equilibrium; showing once more with what delicate precision the insect escapes from its sheath.
For want of a better term I said "escape." But the word is ill chosen; for it implies a certain amount of violence, and no violence must be employed, on account of the instability of equilibrium already mentioned.

If the insect, shaken by a sudden effort, were to lose its hold, it would be all up with it.

It would slowly shrivel on the spot; or at best its wings, unable to expand, would remain as miserable scraps of tissue.

The locust does not tear itself away from its sheath; it delicately insinuates itself out of it--I had almost said flows.