Evening star., 1912-11-03
Animals Used to Test Drugs

Il
of various animals, such as chickens,
dogs, cats, and frogs, to test the efficacy of
drugs.
Ergotlne, tor instance, is tested on chick
ems in an extremely simple way. Should it
fail to turn a chickens comb black, it is at
once known by the experimenter that the
drug is worthless.
Dogs are employed to test hashish. This
is manufactured from female buds of hemp.
the male buds having no particular medicinal
value Hashish administered to dogs in
duces peculiar pathological condition, if
the drug is correctly prepared, which is seen
in no other animal save man himself.
Digitalis, the heart stimulant, is best
tested on frogs. Injecting drop of the drug
into the stomach of the frog, the chemist, by
means of the kymograph, or heart-recordlng
machine studies the changes of the frogs
heart action, thus obtaining accurate knowl-
edge as to the effect of that particular kind
of digitalis.
Curious Scientific Prediction
EVERYONE is familiar with the story
= often told of the great naturalist Cuvier,
to the effect that, given single bone, he
could reconstruct the animal to which it be
1onged. That somewhat similar law of or
ganization runs through the various species
that form families in the animal world is
indicated by quaint case of scientific pre-
diction, to which attention has again lately
been called.
1t appears that Ehrenberg, when engaged
in a study of the minute animals called di-
atoms, found that many species were dis
tinguished by the number of rays they pos
sessed. In the series of specimens that he
had, however, he could find none having,
respectively, 81, %, 30, 81, 81, 80, Al, AZ, A,
45, 46, 48, and 40 rays. Still he predicted
that the missing species would some day turn
up. This prediction has already been veri-
fed for ten of them have since been discov
cred, leaving only three to be accounted
for.
An Ants Sewing Circle
A PARTY of German naturalists recently
= returned from Ceylon have reported
the existence of species of ant that has been
observed in the act of sewing two leaves to-
gether for the purpose of forming a nest.
This report confirms the observations of
the English naturalist Ridley, made in
1890.
They saw row of the insects pulling the
edges of leaves together; then others trim
ming and fitting the edges; and finally the
completion of the work by still other ants
which fastened the edges with silky thread
yielded by Larvae of the same species the
workers carried in their mandibles. 1t is
said that the sewing ants pass the thread
giving Larvae like shuttles through holes in
the edges of the leaves.
Plant that Coughs
A Ii have read of carnivorous plants of
"A laughing plants, and of plants that
weep; but who has heard Of plant that
coughs? There is the authority of French
botanist, however, for the statement that
plant in various tropical regions actually
possesses the power to cough in the most
approved manner. The fruit of this plant
resembles the common broad bean.
1t appears that the coughing plant is
something of crank, that it easily works
itself into rage, and that it has curious
horror of all dust.
AS soon as a few grains of dust are depos-
tied on its leaves, the air chambers that
cover their faces and are the respiratory or
gans of the plant become filled with gas,
swell, and end by driving out the gas with a
slight explosion and a sound that resembles
so much the cough of child suffering from
a cold as to carry most uncanny sensation
to the one beholding the phenomenon.