(xen ) 
seeking what they could devour; and then I was appointed to 
exterminate them. 
A careful study of the state of affairs showed me that they 
were in a place where they could do no harm; on poor scrubby 
land near the margins of forests; an uninhabited region, 
where it would be very difficult to attack them from want of 
men. ‘Troops might perhaps have been taken there, but the 
civil war was just over, and there were difficulties. 
At that time the young locusts were rather over an inch 
long, and more than sixty days old; food was very scarce, 
and winter rapidly approaching. From this I considered that 
few, if any, would attain the winged state and lay eggs; so I 
advised a policy of ‘masterly inactivity,’ which was accepted, 
and they were left alone. The result proved the wisdom 
of this policy, and they all died out. 
Meanwhile news poured in of another invasion near the 
origin of the River Bio-bio, more to the north, therefore more 
to be feared; and on May 26th, at twilight, I reached a wood 
where every tree was coated with such a layer of winged 
locusts that the bark was not visible. Taking a handful from 
the nearest tree, I found to my surprise that every specimen 
had a reddish stripe on the thorax, like A. cancellatum, though 
in other respects they resembled the Argentine specimens 
more than the Chilian ones. Next morning showed that for 
miles round the country was carpeted with locusts innumer- 
able, all with the reddish stripe ; there was no transition, no 
variation. 
The inhabitants of these parts assured me that they found 
a difference between the specimens bred there and those that 
had crossed the Andes and laid the eggs that produced them. 
I can offer no explanation of the matter, neither do I know 
of any similar case. There is no postal parcel communication 
between Chile and London, or I would gladly send specimens, 
Few entomologists would fail to consider the specimens 
that crossed the Andes, those produced by the eggs they laid, 
and the Chilian A. cancellatum, as three good and distinct 
species ; yet they are but one. 
From information obtained there has been no other invasion 
in the memory of man; so A, cancellatum has been in Chile, 
