Year: 1877

In most species of ants the power Of
smell is very keen. l placed ants on
strip of paper, each end of which was
supported on a pin, the foot OF which
was emersed in water. They then ran
backward and forward along the paper,
irving to escape If camel's hair
pencil be suspended just over the paper,
they pass under it without taking notice
of it /; but, if it be scented, say with law
ender water, they at once stop when they
come near it, showing in the most un-
mistakable manner that they perceive
the odor. This sense appears to reside,
though not perhaps exclusively, in the
antenna. / tethered, for instance, a
large specimen of Fornlica lgniperda
with fine thread to board, and, when
she was quite quiet, | approached a
scented camel's hair pencil slowly to the
tip of the antenn9, which was at once
withdrawn, though the antenn@ took no
notice of similar pencil if not scented.
On the other hand, as regards their
sense of hearing, the case is very differ
ent. Approaching an ant which was
standing quietly, have over and over
again made the loudest and most shrill
noises I could, using a penny pipe, a
dog-whistle, violin, as well as the most
piercing and startling sounds l could
produce with my own voice, without ef-
feet. At the same time | by no means
would infer from this that they are really
deaf, though it certainly seems that their
range of hearing is very different from
ours. We know that certain allied in
sects produce a noise by rubbing one of
their abdominal rings against another.
Landois is of opinion that ants also make
sounds in the same way, though these
sounds are inaudible to us. Our range
is, however, after all, very limited, and
the universe is probably full of music
which we can not perceive. There are,
moreover, in the antennH of ants GER
tain curious organs which may perhaps


be of an auditory character. There are
from ten to twelve in the terminal seq


ment of -Ldsius fauDs, the small meadow


ant, and, indeed, in most of the species


which | have examined, and one or TIVE


in each of the short intermediate seq


ments. These organs consist of three


parts: a small spherical cup opening


to the outside, long narrow tube, and


hollow body shaped like an elongated


clock-weight. They may serve to


increase the resonance of sounds, acting


in fact, to use the words of Prof


Tyndall, who was good enough to look


at them with me, like microscopic


stethoscopes. The organs of the vision


are in most ants very complex and con


spicuous. There are generally three


eyes arranged in triangle on the top o1


their heads, and on each side a large


compound eye, containing sometimes


more than 1900 facets between them
Nevertheless the sight Of ants does no
seem to be very good. In order to tes
how far ants are guided by vision,
made the following experiments:


placed common lead-pencil on !;
board, fastening it upright, so as t.
serve as a landmark. At the base


then placed glass containing food
and then put l.. niger to the food
when she knew her way from the glas
to the nest and back perfectly well, sh'
went quite straight backward and for


ward. I then took an opportunity whel


the ant was on the glass, and moved th


glass with the ant on it about thre


inches. Now, under such circumstances


if she had not been guided by sight, sh
, could not, of course, have had an,
difficulty in finding her way to tn
? nest. As a matter of fact, however
: she was entirely at sea, and, after wan
dering about for some time, got back t.
the nest by another and very rounda
, bout route. / then again varied the ex
pertinent as follows: placed the foo
in small china cup on the top OF tn
9 pencil, which thus formed a column
Y seven and half inches high. Whe
> the ant once knew her way she wen
: very straight to and from the nest.
8 then moved. the pencil six inches. Thi
. puzzled her very much; she went owe
t and over the spot where the pencil ha
7 previously stood, retraced her steps Sc,
eral times almost to the nest, and the
!, returned along the old line shown
great perseverance, if not much powe
! of vision. She found the pencil at las
i but only after many wanderings. the
e repeated the observation on thre
e other ants, with the same n
a suit; the second was seven minutt
e before she found the pencil, and at la
a seemed to do so accidentally; the thir
u actually wandered about for no less tina
e half an hour, returning up the pap'
e bridge several times-Fortnightly r
/ UieW.