COMPOUND ANT-HILLS. 281 
_ The signal they adopt is extremely 
varied; sometimes they strike against 
each other with their forehead or man- 
dibles previous to the commencement of 
their march; at other times they appear 
to excite, by the play of their antenna, a 
warlike ardour among their companions ; 
it would appear that in this way a know- 
ledge of their route is communicated, 
for it seems to be fixed at the moment 
of departure, since the army proceeds 
straight to its purpose. What is remark- 
able in the arrangement is, that none of 
the ants composing the troop move con- 
stantly in the same direction; on their 
arrival at the head of the column, they 
make a little circuit en forme de boucle, 
and re-enter the main body, then, as be- 
fore noticed, return to the rear-guard, for 
the purpose of giving instruction to those 
behind. Eight or ten of the Amazons 
seek every opportunity of outstripping 
their comrades ; these form the front of 
the battalion, but this they scarcely 
attain before they fall back into the 
