186 =Mr. Albert Miller on non-migratory Insects. 
It also seems to me, that the array of facts adduced 
here is a justification for the opinion, that instead of 
being an accidental and isolated event, the involuntary 
dissemination of stationary insects will be eventually 
found to be mostly regulated by the periodical disturb- 
ances of the atmosphere, aided by their own locomotive 
powers in some instances, and in others by the habits of 
life which expose them to its constant influence. 
As the ploughshare breaks up the green sward of 
arable land, and disturbs the closely interwoven roots of 
the existing assemblages of plants, so do tornados, whirl- 
winds, and storms furrow the surface of our globe in all 
directions, unsettling and scattering prosperous commu- 
nities of living creatures, and rendering many of them 
for a time the helplessly drifting waifs of an ocean 
‘ Whose every wave breaks on a living shore.’ 
