The Red Cloud chief., 1888-08-17
INSECT DEVELOPMENT.
Strange and Interesting Transformations
Recorded by NatCralists.

ment of insects is to observe the process TO:
oneself. says a writer in the Country Gentle
man. This can easily be done in the case Of
one of our common butterflies, and it would
he difficult to Eai;1c any simple study in nat
ural history of so much interest and instruo.
ton.
1t is best 10 begin with the egg stage. and,
therefore. the first thinc 10 be Gone is to
find the eggs of butterflies. They can
usually easily be focIG, by careful looking,
attached 80 the UIacr sic, ~ the leaves of
plants upon which l.rvai butterflies feed.
These larva! butterflies arc COMMONLY called
''worns;" every one HIS noticed such So
called worInS upon ;hc ic,vcs of cabbage,
tomato and miiiiVccd plants. Ii then, for
example, the leaves 4. cabbage plants be
carefully examined ia cariy summer there
vii DC foind upon them clusters OF eggs
destined IN hatch ard develop into the COM
mon cabbage butterfly. The eggs arc oval
Ii shape. OF u yellow color, and lave ridges
running ita%tagv!Sc. their appearance, as Il
whole, bcin. somewhat like ears Of yellow
corn.
y leaf with eggs attached should be pulled
eff and Placed in /. box with Il glass cover,
such Il cover bottl admi, ing light ana en-
aiding The observer to watch the process Of
-, hSlt.'A-N.tf "a "ttbNi OSAs ,Ac
chalk-box. The sliding cover of which has
been replaced by picceof glass of like size,
IS a convenient form OF box TO use, but any
lin or wooden box with Il piece of window
glass fo- cover Uiil answer.
The icavcS of the c!ohagc-plant bcingthick
and hardy. they Will probably not vi her, if
kept IN a shady place. until the eggs have
Matched. Each egg produces u small green
and white worEi. The worm should at
once be supplied with fresh cabbage leaves;
It will lie foalG to hive 10 lick Of appetite.
1t grows with surprising rapidly. @t;a!ning
within ii week or ten days its full size, in
length an inch or inch and ! half. II at
tachcs itself along the edge of = leaf, and,
with its sharp-n:ting nou;h-parts. Gevours
if bit by bit until it is entirely eaten, when
1t greoGiiy attacks another. Its body seems
swollen by its constant ssJrging. The truth
Is thai it il TO pass into Il resting condition,
when it takes no food. and il nust now i'm
prove its tine So as 10 gather strength to
last it in its period of abstinence.
At the end OF ten OF twelve days the worm
IS ready 10 pass into this resting stage
what is called the pupa stage. AT this time
it will be seen to abandon its Leaf and crawl
about the box. somewhat eagerly, as if
searching for something. This uneasy ac-
SNLlN LIN tbIttlIuc ~ SCiiic i.tAlt. DCl lt.ldl-
y, as if having found a suitable place, it
proceeds TO spin Z net or web. III which it
may suspend itself daring the approaching
period Of inactivity. This net is not Il CO.
coon. such as the larva of some insects spin,
but a slight web serving merely TO suspend
the pupa. The extreme appearance now
changes. The bright green color becomes
dull, and several rings into which the skin of
the worm is thrown become less distinct,
ard finally it assumes the characteristic
pupa form-an OblOng. angular body. more
pointed at ont end than the other. What
has taken place is the Noting of the SKIN,
that is, the skin Is separated from the body
end becomes simply a firm, hard case in
which the living insect is contained.
In this pupa stage-now often called .
chrysaiis-i it remains for ten or twelve days.
OF course all the while important changes
are gong on within; the energy stored up
during its period of hungry activity now
serves to carry or those vital processes that
made the dull and seemingly lifeless pupa
succeeded by the sprightly, handsome but
,eray. These changes affect the entire
structure Of the animal, internal scarcely
less than external: the butterfly has a diff
ferent nervous, digestive, circulatory, ETC.,
system than the larvl
Al l4SJ tLc UuttcTuNc LicIScS liOm tuc pup0,
the wall of the latter breaking away at one
end. probably by the growth and movements
of the insects within. 1t is one of our plain
yellow butterflies: yet one can imagine that
it has quite a triumphant bearing as it
emergcs from its confinement. 1t soon eX-
tends its wings, and after a few ~fiutters,
if allowed to escape, scars away.
Such is an outline of the development Of
insects, in which the metamOrphosis is CON-
~plcted-that is. insects which. besides the
egg stage. pass through three states, named
successfully. the larva. pupa and image, or
perfect insect. But i'll many insects tho
transformation is incOmplete-that is to
say, the I2ctamorphOsis is not SO marked
the several states are not so distinct.
Take, for instance. the grasshOpper. In
this insect both the larva and pupa resem-
Bile the perfect insect in form, walking and
feeding in the same manner. and differing
chiefly in the absence of wings, though even
the wings are present, in rudimentary form,
in the pupa. And there are groups of in
scc:s in which there is no mctamorphOsis at
all. These are of the lower orders, and in
cludc the insects unfavOrably known as
lice. In these orders the insect, when it
energies from the egg. is quite like the full
grown specimen, except in size.
AItSt-dii. Tue ucVciOpUuenI Oh tne butterfly
and the other insects Of complete meta
morphosis is no more wonderful than that of
other animals. The transformations through
which the insects pass are in NO essential
respects different from those through which
other animals pass in their development.
The chief difference is that in the insects
these transformations take place after the
egg-stage, while in many other animals-as
the birds and most repciles-thcy take place
within the egg. In the insects the egg is
very small, and there is not enough food
matter contained IN it for the growing en-
bryO. 1t therefore breaks through the egg,
and is able to seek food for itself. But in
the birds the egg is large, and has a supply
or food sufficient for the nourishmcnt of tho
embryo until it has attained full structural
development. Hence it goes through its
transformations within the egg. In the in
sect the development is for o time arrested,
80 that the larva can gather a supply of
food, both for its immediate wants and for
gaining q store of energy for the next stage
IN its hfc-histOry. In the birds n most
other animals the development proceeds
without interruption until the young is
brought forth.
An Imperial Abbess.