The record-union., 1894-06-23
SEVENTEEN YEAR LOCUSTS.
Entomologists Call Them Cicada
Septemdecim.
Curious Habits and Customs of These
Noisy Little Insects, Which Fortu-
nately Do Not Make Their Appear
ance Except at Long Intervals-The
Impression That They Are Destruc-
tive to Vegetation is wrong-How
They Make Noise.

They Make q Noise.
A curious fly, belonging to the family
of the CtcadGriGe, and the sub-order of
1HemipteTa, or half-winged or gauze-
winged insects, is now making the resi-
dents of large territory miserable by
its monotonous screeching. Fortunately,
it goes to sleep at night or the plague
would be as unbearable as that Of the
ancient Egyptians. This insect is COM
monty known as the seventeen-year
locust, for the reason, possibly, that
there is a common custom of calling
things by names that do not belong TO
them. For this is not locust, which is
member of quite different family,
known Orthopteya, and is so closely re-
lated to the common grasshopper as to be
taken for it by all but scientific people.
Every summer the song of the harvest
fly is heard sung to its mate, who, unlike
other females, has no voice Of her own,
and is content to live a quiet life and
make no noise in the world. This song
is made up of one long -drawn-out note,
shrill but soft at first, gradually increas-
ing in its crescendo, and maintained for
few seconds, when it gradually loses its
force and subsidies into a low note until it
is heard no more, until, at an interval OF
minute or so, it begins again, and so
continues the whole day long.
This sound is the effect OF vibrating
septum drawn tightly over frame like
semi-globular drum, or, in fact. pair of
them, under the wings Of the insect, and
this mem brane, acted upon probably by
air drawn in and forced out OF the drum,
makes the strident sound uttered by this
insect. This sound is the effect of several
hundred vibrations OF the parchment
like septum per second. 1t may be bear
able by strong nerves when there are but
few in the concert, but when there are
millions in it, and the performers occupy
every branch and twig of every tree and
bush for miles around, the hubbub is in
describable, except as a sound that shakes
the ground and pervades the whole air,
drowning one's voice and deafenlng the
ear. Fortunately, 1t comes but once IN
seventeen years.
Its last appearance was in 1877, when it
extended from Troy, on the Hudson,
through Connecticut, New Jersey, Penn
sylvania, Virginia and the District of Co
lumbia. 1t has again returned IN due
time, having completed its term of inn
prisonment and come to perpetuate its
race and revisit the scenes OF its birth.
For it has not been far away. 1t has been
quietly feeding upon the roots of the ap-
pie and the oak trees, possibly never
straying from the first selected tree, do
ing no harm, but fulfilling its curious
purpose in nature OF making UP for sew
enteen years of silence by terrible din
when it gets the chance. And then it
dies happy.
1t is a stout bodied insect, with broad,
gauzy wings. 1t is far better looking in its
few days OF maturity than in its previous
stage, in which it is homely grub or an
ugly pupa. But it has the advantage of
being well behaved and a modest, silent
creature. strictly devoted to its own busi-
ness, which is to burrow in the ground
for seventeen long years. During this
time it craWls along the roots of the trees,
to which it attaches itself, puncturing
them and sucking the sap. 1t has not
been certainly known that the locusts do
any serious damage, although we'll
known entomologlst, lady, discovered
them quite numerously in pear tree,
which had been dug up on account OF its
mysterious failure to grow, ana her re-
port states that 1.-THE larvae OF this insect
were found in countless numbers on the
roots, engaged in sucking the sap, and
twenty-three were taken from root
yard long and an inch III diameter" Bul
as it has not been found that any speciat
"
they appear in great numbers, this case
may be taken as exceptional. Doubtless
the moles in their burrowlng find and
devour them in great numbers, and thus
keep them in safe subsection.
The grubs stay near the surface, not de-
scending more than six or eight feet,
making circuitous burrows with their
strong forefeet, well adapted for this pur-
pose. AS soon as they reach root they
follow it. feeding on it as they go, and
changing from root to root as they find it
necessary for fresh supplies. Doubtless
the damaged roots die, and are replaced
by new ones, without much injury to the
trees. Thus they live and await the stage
of maturity. AS this approaches they
gradually work to the surface, burrowing
their way and filling the passages behind
them with the earth dug out in front.
This is perceived by the discolored earth
filling the burrow behind the insect, and
the last place of rest, where it makes its
transformation, is only a few inches i'll
length, close to the surface of the ground
and lined with sort of cement, covered
with waterproof varnish, to make it
dry and comfortable. On warm, sunny
days the insects have been found peeping
forth, as if curiously surveying their fu-
ture scene of life and gathering informa-
ton about it. 1t has been observed by
Mr.. Rathvon, a skilled entomologist that
when the ground happens to be wet these
insects. impelled by instinct, build up a
burrow, projecting above the surface, in
which they take refuge when the ground
may be overhowed by heavy rain.
When the proper time, which Solomon
tells us every creature knows by natural
intuition, comes, the mature insect, fully
provided with wings, crawls out of the
ground, always at night, and seeks tree,
up which 1t creeps, and taStens itself by
its strong, sharp claws. Then it is
soft, whitish grub. In this con-
dition the skin dries, cracks and
bursts open along the back, and the per-
feet cicada creeps out through the rent,
leaving the empty shell still adhering to
the tree as a semi-transparent, parch
ment-like skin. Then it emerges into
the open air, and, after a few preliminary
attempts to spread its wings, by which
they are stiffened and dried, the fly rises
in the air with strong swift flight, and,
selecting its temporary home in which to
pass the few days of its perfect stage, pro-
ceeds TO active business. The female,
hearing the call of its mate, selects it's
partner and makes preparations for de-
posting its eggs. This is done on the
small branches of the trees, the eggs be-
ing deposited in neat double rows, paral-
lei, and arranged up and down the bark.
Many such rows are made on each twig,
so that the majority of them dry and die,
leaving the tree often bare and dead, ap-
parently, but wholly SO as to the injured
branches and twigs. The fly is not known
to feed in this stage, but simply performs
its parental functions and then dies.
The letter ''W'' is quite plainly marked
on forewings of the mature insect and
some superstitious persons have greatly
alarmed themselves, most unnecessarily,
by thinking this meant war. Others,
more sensible, think it means warm
weather, and prepare their thin clothing
for Immediate use. Other persons have