118 
ANIMAL INTELLIGENCE. 
parent confusion is that scarcely a single Hypoclinea gets away 
with a pupa or larva. I never saw the Ecitons injure the 
Hypoclineas themselves, they were always contented with de- 
spoiling them of their young. 
The columns of this species 6 are composed almost 
entirely of workers of different sizes ; 5 but, as in the 
species previously mentioned, 6 at intervals of two or 
three yards there are larger and lighter coloured indi- 
viduals that often stop, and sometimes run a little back- 
ward, stopping and touching some of the ants with their 
antennae , 5 and looking 6 like officers giving orders and di- 
recting the march of the column.’ 
Concerning the other habits of this species, the same 
author writes : — 
The eyes in the Ecitons are very small, in some of the 
species imperfect, and in others entirely absent ; in this they 
differ greatly from the Pseudomyrma ants, which hunt singly 
and which have the eyes greatly developed. The imperfection 
of eyesight in the Ecitons is an advantage to the community, 
and to their particular mode of hunting. It keeps them to- 
gether, and prevents individual ants from starting off alone 
after objects that, if their eyesight was better, they might dis- 
cover at a distance ; the Ecitons and most other ants follow 
each other by scent, and, I believe, they can communicate the 
presence of danger, of booty, or other intelligence, to a distance 
by the different intensity or qualities of the odours given off. I 
one day saw a column of Eciton hamata running along the foot 
of a nearly perpendicular tramway cutting, the side of which 
was about six feet high. At one point I noticed a sort of 
assembly of about a dozen individuals that appeared in consul- 
tation. Suddenly one ant left the conclave, and ran with great 
speed up the perpendicular face of the cutting without stopping. 
It was followed by others, which, however, did not keep straight 
on like the first, but ran a short way, then returned, then again 
followed a little further than the first time. They were evi- 
dently scenting the trail of the pioneer, and making it per- 
manently recognisable. These ants followed the exact line 
taken by the first one, although it was far out of sight. Wher- 
ever it had made a slight detour they did so likewise. I scraped 
with my knife a small portion of the clay on the trail, and the 
ants were completely at fault for a time which way to go. 
Those ascending and those descending stopped at the scraped 
