Year: 1873

| It's embarrassment; 1t returned, placed IL
self across the caterpillar, as if on horse
back; with its two middle feet it embraced
the body of it's victim, raised it against its
breast, and managed to walk on the four
feet which were at liberty thus it soon
crossed a walk of six feet wide, and laid
its prey against a wall.


Investigations have been made regard
ing the jumping insects of the order Or
thoptera-the weight which crickets and


grasshoppers can raise when jumping.
To prevent them using their wings, MI.
Plateau tied them and the elytra or outer
sheaths with thread. The burden was


a ball of wax ballasted with morsels of
| lead, which was hung to thread TED
round the thOrax; as much lead was add
ed to the wax until the insect could only


raise itself an inch from the ground. The


ball and the insect were afterwards
weighed the latter having been
made insensible by the fumes of
ether Crickets Of the larger kind raised
about one and a half their own weight;
the smaller ones three or four times their
weight The grasshopper differs from the
cricket in having longer and thinner legs;
the green variety weighing about two and
a half grammes, can only raise weight
equal to it's own, confirming the law that
the muscular force Of insects increases as
their size diminishes. When allowed to
Jump freely, crickets describe curve in
the air similar to all projectiles. 1t is
curious that the amplitude Of the spring is
the same for the large and smaller kinds
alike This result was foreseen by the
celebrated naturalist Strauss -Durckheim.
| In his work on "The Comparative Anat-
Omy of Articulated Animals" he estab-
fishes the point that two animals of SINH
lar form, but of different dimensions, will
Jump the same height above the point
where lies their center of gravity at the
moment when they quit the soil. lie
takes as an example the cat and the tiger,
and adds that the same conclusion is ap-
plicable to crickets and grasshoppers.
The principle which serves as a basis for
this theory is, that the motive power OF
animals increases with the section and not
with the volume of the muscles. 1t de
pends only on the number of
fibres of which the muscles are
composed; from whence it follows
that it ought to be in proportion to
the surface of the section Of these organs,
whilst the weight of the animal is proper
tiOnal to their volume. The weight aug
ments more rapidly than the motive


power and the relation between this
weight and this force becomes the more
unfavorable as the animal is larger Other
naturalists who agree to this as whole
do not consider it to be an absolute gener-
al law. Among the insects that dig or
burrow in the ground, different plan
was tried to see their power of pushing
forwards They were placed in a card
board tube, which had been blackened
and made rough for the feet; at one end
transparent plate of glass was fixed to
horizontal level. Perceiving the light be-
fore it through the plate which barred its
exit, the insect when excited pushes with
all its strength; the plate gives way, the
lever turns and raises at its other eXtrem-


pulley, and into which the sand is poured


as before. In this way the oryctes,


weighing about forty-six grains,


pushed three or four times


its own weight, whilst the little


onthophagus moved eighty or ninety
times that amount The experiments in


the way of flying lead to the conclusion


that insects employ much less muscular


force in that way than in drawing or push
! ing; perhaps it is that, unlike birds, they


are not intended to carry large weights


through the air. A ball of soft wax of
weight little superior to what the insect
might be expected to bear, was fastened


round it's body, and it was tried as to
whether it could support this in the air:
if it fell, the size was diminished. Among
various insects belonging to the five orders
of ColeOptera (beetles), it was found that
thev could raise from One-slXth to double
their own weight; the common lily could
manage triple that amount Iet the Hight
of insects is so rapid that some can dis
4l.o bot them
certain kinds of flies are said to be able to
pass race-horse or a locomotive going at
full speed. If we inquire why the smaller


species are the stronger, the answer may


be that their way of life necessitates
it. Thus the hardness of the soil
is the same to all the burrowers;


the grains of sand which the larger


can easily displace are rocks to the small
| er ones; and, comparing them with ami


mails, the mole and the rabbit require


much less strength to force passage than


the ant. The prodigious leaps OF the


cricket, the locust, and the grasshopper
would, in the same proportion, make


lion spring over half mile. Not less
SURPRISING is the power of destruction in


certain classes: the termites have under
mined whole towns which are now sus-
pended over catacombs Such is the case


with Valencia, in New Granada; La


Rochelle is menaced by the same fate.


The larve or the sirex pierce through balls


of lead with their mandibles. During
| the Crimean War, packets OF cartouches


were found the conical balls OF which


were perforated in various parts. Ihe
little African ant can raise mounds OF clay


five yards high, and of such solidlty that
the wild cattle stand on them to explore


the horizon. Such edifces are thousands


of times larger than their architects,


whilst the pyramid of Cheops is but


ninety times the height of man.


Another subject which has engaged the
| attention of naturalists of late is the
strict relation which exists between the
| habits, manners, and mode of life in in
sects with the conformation OF their
organs. Mr. Darwin has acknowledged the


organic adaptation of species to the con-


dition of existence; but he thinks that,


owing to their want of exercise on one
| side, and natural selection on the other,
| these organs may undergo deep and hered-


itary notifications. Thus he explains the


want of wings in many coleopterous in
sects which inhabit the island of Madeira;
| they lose the habit of flying, because, if
they used it, the wind would carry them


away into the sea, and the race would
soon disappear. Thus, winged insects


made for flight can transform themselves,
in time into walkers or swimmers.


If we consider the locomotive organs of
insects, it is easy to see that broad mem
bers which can be converted into oars be-


long to swimmers; when they are short


and indented, they are to be used like


shovels and pickaxes by the burrowing
| tribes. Though the mouths of insects are
] formed with the same number of aDnli-