The Chickasha daily express. (Chickasha, Indian Territory [Okla.]) 1899-current, 1908-07-11

the attacks Of numbers OF predaceoua
and parasitic enemies. Among the
former are Syrphid flies, two-winged
insects, which place their eggs among
the colonies, the eggs Matching into
hungry maggots which consume large
numbers OF lice The s0-called lady
birds" beetles belonging to the family
Coccinellidae, do the same thing. their
gruhs or young deVouring enormous
numbers Of aphids.
Among their parasitic enemies the
most prominent, in fact the parasite
through whose work in normal years
both Toxoptera and Macrosiphum arc
kept in check, is a small iOur-winged
hymenopterous insect, Lysiphlebus tri-
tici which, upon the advent of warm
weather In the south last summer, rap
idly increased and reduced the hordes
Of lice. This insect we found In the
north, last summer, and reared it re
peatedly from Toxoptera. Unfortun-
ately l.. tritici does not reproduce
freely al low temperatures; below
5R degrees F. it is said to be inactive,
OF, as Webster puts it. it is active only
when the temperature Is Is degrees
above that at which the green bug
breeds freely. The method Of attack
on the part Of this parasite is shown
in Fig. Of one OF our Illustrations.
and represents an individual Of
Iysiphlebus sp. in the act Of oviposit-
ing in a specimen Of NJ granaria.
Normally l.. tritici, as observed BY u.s.
approaches Tox0ptera very deliberate
Iy, generally from behind, though fire.
quently from the front, and Oviposits
with but little, or at least without ef-
fectiye resistance on the part Of that
louise; hut MaerosfphuIn appears to
be more on the defensive and foe
requiring fner taetiea This may ac-
count for the method OF attack as
shown. The egg placed in the body
of the louise, hatches IN a few days.
The iarva feeds upon the tissues Of It's
host, preventing, it Is claimed. any
great production Of young, and in this
way, even before the death Of It's host
] doing much to check the increase Of
| the pest. Later, about q week from
Matching possibly the parasite has at
! tanned its full size. and with the prop
4 er light and magniflcation. can be dis
i tinguished through the body wall o.
its host, Fig. 3. The body Of the louise
swells, the individual dies, the ski
darkens and hardens, and In shor
time the little parasite smerges as
/ four-winged fly from q round hole GU
IN the abdominal wall Of the dead n
sect, Fig. 4, prepared to mate ant
= carry on the good work, II only tn
: weather win permit. Millions Of thi
genus Of parasites are in our fields
i working not only upon Toxopters
y when present, but upon some othe
4 plant lice. notably Macrosiphum. an
in ordinary years are the princips
g means Of keeping these pests
w check. II Is an encouragement {
ef know that yonng lice destined to b
IA winged are frequently parsltized
~ hence, when the Image migrant files {
90 other fields, it frequently carries tn
er beneficial insect With II. It Is worth
d, Of note also IN connection with th
IS. subjects OF parasitisms that We And
-e- the north climatic conditions whic
IN are directly opposed 10 any disastrol
IS outbreak Of grain plant lice. II oths
Mt words, we have cold winters and var
re summers, the flrat factor p1eyentln
on any undue Increase Of llce unastends
so by parasitlam, and the warn sn1
Is. nlers allowing q q rapid inereai
as 0f parasites before the lice hal
ch gained much headWey.