66 INSECT OR REACTIVE-PASSIVE LOCOMOTION. 
In the above extracts Pettigrew has borne unconfcious 
teftimony to the importance of the infed world in their 
relation to aerial navigation, and in a manner prophefied 
of its accomplifhment through their agency. 
To the fuperficial gaze of man, Nature frequently 
feems inconfiftent; but harmony reigns through all the 
works of God. Seeing that the portion of the atmofphere 
neareft the earth has the greateft denfity, being the loweft 
of the air ftrata, we fhould naturally fuppofe it beft fitted 
for the heavieft of the flying creatures. Inftead of this, 
we find the heavieft birds neareft the clouds, and infeds 
and the lighted of flying creatures neareft the ground. 
But the reader who has followed me thus far will be under 
no lofs to account for this. Force, though vifiting the 
furface of the ground, and holding conftant revels in the 
ftratum neareft the earth, dwells in the fkies, defpite the 
fabled flEolus, with caves on earth. And the birds, as we 
have feen, find inftindively the forces where they are. 
But the infed world of dragon-fly type are quite inde¬ 
pendent of the birds and bird methods of navigating the 
air: they are the pofleflors of an independent fphere of 
their own. The winds of the firmament they neither court 
nor ftiun. Their locomotion goes on as well within the 
ftifling atmofphere of a chamber of cc dead air ” as in the 
open, where the breezes ftir the flowers. No mofquito 
ever had one bite the lefs becaufe of the deadnefs of the 
air he was getting his repaft in: no bee ever mifled the 
L of 0 . 
