New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1882-07-30
TIE PLlGUE or cArERPILLARS.
From ne Loadon Spectoior.

Firm, ne LO.idOl Spectator.
Since the number OF individuals, on the average,
remains the same. an enormous majority SAY,
ninety nine hundrrdths die without continuing
their species. Every insect mas ouI Stages 10 pis0
through in q year. sometimes IN half year or less,
viz egg. caterpillar. pupI and winged insect; IL IS
in the caterpillar stage that all the eating Is DONE
The caterpillar and the winged si,re' pelhg ti no
stages of exposure are those IN Whlch most Oh tIo
thinning takes place; and the latter is the more
impnriant stage this respect he ause ny the llnc
q caterollIar has crown large enough 10 he made
satisfactory meal o. IT has already done much ms
chef. In the caterpillar stage the thinning cHeclcd
bv birds tree-bugs carnlvoiOus caterpl aIs etc Is
cn0rEous. Ichneumon flies are not To he lncIuded
for though hcy Kill, death does not AXE place tlll
the caterpillar is full feo ana, IN me llhc
the yOnng parasitic family they provide II WIN mas
probably increased the caterpillars voIactty. In
The winged STAGE also. immense numbers are de-
stroyed by birds and 10y bats ana carnlVOrous IN
serts Eut none OF these checks OH multIp lIcation
nor all together appear to I've suhclently Narlapie
TO account that sudden increase ID caterplilarS
i'm some years that Is spoken oi ~ q plague; the
question arises whether we do not ina Such chrrk
i'm the @ratler ! doubt whether any one VINO mas
not been practical cntOmOlOgIst has an adequate
concept on of the thinning effect exercised by un
favorable weather on insects IN the winged state or
the cOrrespondngly qmckening elect oil weather
that is favorable. The effect Is concentrated, be
cause the existence OF insects III tins stale - hrle-
a few DAYS for an individual. few we, rs for a
whole speres-and il Is strong becase III TINS stage
they are so sensitive to IT, IL Is not merely mat
rough weather destroys them, ana that IN WINDY
weather they do not fly, but the mere absence 81
sunshine is enough to prevent many species from
moving at all Like the pale primroses,' but IN
different seuse, they
"Die unmarried. ere they can behold
Bright PhGbus in his strength
The sunless summer of 1850 nearly exterminated
from some Of the Sussex and Hampshire woods S'v
cral species which mad formerly been pientliul
there. a rainy fortnight may produce snch an
effect on - species the other hand, hot fort
night az tine right time may foster an immense IN
crease III the number of fertile eggs land Even " men
the species does not require sunshine greater or less
warmth makes a vast difference IN the numbers on
the wing: i'm hot weather. the l;ghtest touch of the
brqtiup-stick brings them out in swarms while In
ordinary weather they are difficult TO rouse
need scarcely add that the circumstance that
a principal cause of insect plaques the weather
Is beyond our control affords argument against
the use of such means of keeping them under as are
within our power to influence. Chief among these
means seems to be the preservation of those viva
rlous inhabitants OF our woods and gardens. some
shy some lmperiInent, but all teAcept sparrows
delightful, our wild birds