Year: 1877

One Of the most interesting problems
about ants is, of course, TO determine
the amount of their intelligence. In or
der to test this, it seemed TO me that one
way would be TO ascertain some object
which they would clearly desire, and
then TO interpose some obstacle which
little ingenuity would enable them to
overcome. With this object in view,
placed food in a porcelain cup on a slip
of glass surrounded'by W alter, but acces-
sible to the ants by bridge consisting
OF strip Of paper two-thirds of an inch
long and one-thnd wide. Having then
put f. nigra from one of my nests to
this food, she began carving it of, and
by degrees a number of friends came to
help her. then, when about 25 ants
were so engaged. moved the little pa
per bridge slightly so as 10 leave chasm
just 50 wide that the. ants could not
reach across. They came to the edge
and tried hard 10 get over, but 1t did not
occur 10 them TO push the paper bridge,
though the distance was only about one
third ofan inch, and thew might easily
have done so. Alter trying for about a
quarter of an hour they gave up the at
tempt, and returned tome. This re-
pca.ed several times. Then, thinking
that paper was a substance to which
they were not accustomed, | tried the
Same with a bit nf straw one inch long
and one-eighth of an inch wide. he
result was the same. repeated this
twice. Again placed PARTICLES of food
close 10 and directly over the nest, but
connected with it only by passage
several feet in length. Under these cir
cumstances IT would be obviously saw
ing Of time and labor TO drop the food on
the nest. or al any rate 10 spring down
with r., so as To save one Journey. But
though | have frequently tried the ex-
pertinent, my ants never adopted either
OF these courses. Karranged m tiers so
that the glass on which the food was
placed was only raised one third Of an in ch
above the nest. The ants tried 10 reach
down, and the distance was so small
that occasionally, If another ant passed
underneath just as one was reaching
down, the upper one could step on its
back. and so descend; but this only hap
pened accidentally, and they did not
think of throwing the PARTICLES down.
nor, which surprised me very much.
would they Jump down themselves. /
then placed heap of fine mold close to
the glass. but just so far that they could
still not reach across. 1t would have
been, Of course, quite easy for any ant,
by moving a particle of earth Tor quar-
ter OF an inch, TO have made bridge nv
which the ioo5 might have been reached.
but this simple rxpedient did not occur
TO them. On the other hand then
put some provisions in shallow box
with glass top, and single hole on
one side, and pu; some specimens OF
Lasius niger 10 the food. As soon as
stream of ants was al work. bu,ilv car
rying supplies off 10 the nest. and when
they had got 10 know the wav thorough
ly, poured some mold in front of the
hole so as 10 cover il rp TO depth of
about halt an inch. then took out the
ants which were actually in the box.
As >oon as they had recovered from the
shock Of this unexpected proceeding on
my part. they began to run all round
and about the box, looking for some 9th
er place of entrance. Finding none.
however. they began digging down into
the earth ust over the hole. carving
oil the grains of earth one bv one, and
depo>Iting them, without anv order. all
round al a distance of from half an inch
TO SIX inches, until they had excavated
down TO the doorway, when thev again
began carving Off the food as be tore.
This experiment repeated on follow
ing DAYS three or four times. ALWAYS
with the same result. As evidence
both Of their intelligence and of their
affection for their friends. il has been
said by various observers that when
ants have been accidentally buried they
have been very soon dug out and res
cued by their companions. Without
for moment doubling the facts a
stated, we must remember the habit
which ants have of burrowins m lcose
fresh soil. and especially their practice
of digging out fresh gallerie. " hen their
nests are disturbed. II seemed 10 me.
however. THAI 10 would not be difficult
to test whether the excavations made
BY ants, under the circumstances, were
the result Of this general habit, or real
ly. due 10 the desire TO extncate their
friends. With this view I tried ssD,h