Shenandoah herald. [volume] (Woodstock, Va.) 1865-1974, 1879-07-16
FARM AND FIREsIpE.
The Cabbage Butterfly and its
Ravages.

get rid OF them. / have tried salt, salt.
petre dissolved in water and carbolic
acid, with apand water, and still none
OF these check them. Can your ento-
mologist tell where they came from,
and what will destroy them and oblige
Butler, Ill., w. A. Y.
The best answer we can make YOU on
this subject is in the words of Miss EN-
lily A. Smith delivered before the Wis
consin Horticultural society, at Green
Bay last week. as follows:
Pieris rope S.
Among other insects which have made
their appearance to a serious extent.
the cabbage butterfly is PROMINENT
Much has been written on the habits
and destruction Of the insect in the Eas-
fern States, and each year entomologists
have apprehended their appearance in
the West, but it was not until 1877 no.
tceably common, and IN the centre of
the State OF Illinois, '7S first witnessed
the power Of its destructlveness. The
LIE history of the insect, briefly stated
IS as follows: For many years it has
proved a great impeachment against
growing members Of the Crucifere fami.
iy in England and was confined exclu-
slvely to Europe until the wear 1859.
when MIR. Bowles captured specimens
in the vicinity of Quebec, they having
been conveyed while in the Larvae state
on heads OF cabbages, since which time
they have spread with great rapidly,
becoming acclimated at once, and being
both wonderfully prolific and hardy has
been considered one of the most de-
structive OF insects. The eggs are placed
lndiherently on the under side of the
leaf. sometimes appearing upon the leaf
stalks, are very small and but slightly
attached to the leaf, are not readily
perceived, since they differ slightly in
color from the leaf itself. These eggs
hatch in about one week after they are
laid, the young worms eating an open
ing through the shell OF sufficient size
to enable it to crawl therefrom. The
first act of the young worm is to eat the
shell of the egg from which it has been
Matched. DR.. Fitch, the eminent ento-
mologist Of New York, states that this
act requires five hours, when the worm
remains at rest for few hours.
The young insect finds itself at once
upon its food plant, and weaves for itself
a mat of carpet upon which it remains
while partaklng food. THIS mat is made
from threads Of exceeding fneness, and
comes from the glands on either side Of
the alimentary canal, from which it is
in reality an appendage. These threads
issue'from the mouth and are fastened
at short intervals to the leaf until a
thin film is formed sufficient in thlcknes.
to enable the insect to secure a firm
grasp upon the leaf. If nothing occurs
to drive the worm away, it remains in
this position until the food Is exhausted
within its reach, when it moves to a
fresh spot and again constructs a foot
ing OF silk. The caterpillar mouths three
times, ia then one and a half inches
long, pale green. finely dotted with
black, yellow stripe down the back
and row of yellow spots along each
side IN line with the spiracles. When
about to transform it leaves the plants
on which it has been living and fastens
itself on the under side of some stone,
plank or fence.rail where it changes into
the chrysalis or pupa state, from which
the butterfly emerges later. In the
summer the insect remains in the pupa
state one week only, thus making its
transformation from the disposition of
the egg to the image in four weeks, since
the development Of the embryo requires
one week and the larval form is COM
pleted in fortnight. This is, however,
only when all is favorable, since they
hare been known to remain from Au-
gust 81 to December 8, or 100 days in
the pupal form, and Joseph lie Admiral
succeeded in retaining one specimen
from September to May % or 255
days.
The butterflies are generally supposed
TO hibernate during the winter months,
but in the instance cited above prove
variation. lam inclined to think the
insect varies with the locality since
those bred by myself, in Peoria during
the years III aud '7S remained without
exception in the pupa state and many
chrysalides were gathered from thoir
covered retreats during the winter
months, and on the approach Of warm
weather changed o the Image. The
reason attributed TO the Information Of
the butterfly was because the chrysalis
was without a covering or. protection.
There are two .broods each year. A
prominent trait OF the insect is the
quiet peaceful disposition Of the larvs.
They avoid intrusion and do not sncroach
upon each other, or upon insects of other
orders. They are capable of withstand
ing great hardships, are not affected
by changeable weather, and neither
degrees Of temperature or privatlon OF
food for time affect them. This re-
markable tenacity to life renders arti-
fetal remedies less effectual, and
hellebore, lime ashes and various propos-
ed plans which prove so eficacious with
the Tenthredinous larvae have 10 effect
upon these. The French call it the Yer
du Coeur,' or heart worm, because they
bore into the heart of the vegetable and