The Washington herald. [volume] (Washington, D.C.) 1906-1939, 1910-05-01
Nv J. CLINTON RANSOM.


eases Of men and animals and incidental
~ revises country-bred ideas on the sub
sect OF "chiggers'' is contained in recent
publication from the busy source Of infor-
NATION on the Mall
Incidentally this publication solves a
good many mysteries in dermatology and
Is OF quite as much interest 10 the medi-
cal profession as the farmer who raises
wheat straw and the common sailor who
sleeps upon Il IN HIS humble bunk aboard
ship. The investigation which has re-
suited in dinerentiatlng and giving the
life history OF a parasite with the high
sounding name Of pediculoides ventrico-
gus takes far-reaching sweep, and is
hardly less remarkable in results than
the work OF Halley in plotting the course
Of the great comet and announcing to
The world that the celestial wonder was
really part OF the solar system.
Parasite One of the ChigEers.
In certain parts OF the United States
people are affected by an itching and
eruptive disease Of the skin which they
attribute 70 "chiggers," in popular YER
nacular a small insect that attaches 70
the skin, burrows therein. and causes
itching and Inflammation. with consider
able discomfort and irritation. CHG
gers" may be one OF several animal para
sites but It now appears that one OF the
most common OF them is the pedIculoides
ventrlcOsus, which does not attack man
at all when It can find other food. and Is
really one OF the most useful microscopic
beings in the universe. Were It not for
him and his tribe the nations wheat.
barley and oat crops would be destroyed
before ripeninC or I'm tho kernel. and i'm
his busy little way this parasite Stays
millions OF the grain moth and wheat
stem maggot every year.
The double Greek name applied to the
parasite. which is too minute 20 be seen
by unaided vision. has reference TO the
number and arrangement OF its feet and
the curious distenslon OF its abdomen
during the gestating period When IN the
pursuit Of it's usual course Of life this
minute insect preys only upon the wheat
moth which Il surely kills. and the Joint
worm. Of which it is the sworn enemy II
is only when the parasite Is carried in the
straw with its prey 10 the skin OF human
beings and animals and when In the
throes Of starvation that It seeks 10 null
tiply its species az the expense OF the
human race.
studies of the Parasite,
The existence, life and habits Of this
curious parasite have been studied
through two lines of investigation both
of which started almost by accident
F. n Webster, IN charge Of cereal and
forage insect Investigations in the De-
partment OF Agriculture. back in 1852 re-
ceived in his laboratory a sack OF wheat
infested with the larvae Of the grain moth
from Southern Illinois. In making ex-
perimcnts with this grain AR Webster
discovered that many Of the moths in the
grain were either dead or expired during
his observation In a manner quite unac-
countable under the circumstances.
Investigation proved the presence Of the
parasite and all his destructive tendencies
upon the moth. Further experiment and
investigation established the existence or
the parasite over a large portion Of the
country, and the department chief came
to the conclusion that the only reason
why the grain moth was not rapidly an
initiated was the existence % other In
sects and parasites and conditions OF
temperature which discouraged the opera
tons OF the pedicuoldes ventricosus. In
other words. other enemies Of the grain
moth or stem worm, not so deadly. an
ticipated the movements Of the parasite
and shut him ont. Besides, the tempera-
ture has an important effect upon the
little fellow, as he cannot work well ex-
cept when the Thermometer registers so
degrees or higher.
This line OF investigation pursued many
years in all parts OF the country estab-
hshed the utllitarian features OF this mi
mute being which occupies the other end
Of creation from the blazing mystery just
appearing in the morning sky.
Feed Upon Sailors.
A year or two ago several sailors upon
q ship in the harbor Of Philadelphia were
attacked by a peculiar skin disease. It
happened that one Of the physicians Of
the Marine Hospital Service was assigned
% treat the cases and investigate the
cause. This investigation traced the dis
ease 70 this parasite. which had been
conveyed to the brig in the straw Of some
new mattresses with which the vessel
had been fitted out
In a boarding house IN PHILADELPHIA
about the same thing happened. and the
victims had also slept upon mattresses
fresh from the factory
In Baltimore a similar occurrence called
for the investigation Of physicians there.
In all these cases the source Of the straw
was traced to New Jersey and to Illinois
where the parasite and his principal
source Of food, the grain moth. was spe-
cially prevalent that year. It was dis
covered that the grain moth and the stem
worm had both been carried in the straw
and put into the mattresses. The para
site, driven by pending starvation to an
exodus from the straw, walked through
the ticking and the sheets to the bodies
OF the men and found a new and strange
form or food. Burrowing in the skin re-
suited in tho unknown skin disease, and
new chapter was opened in scientific
dermatOlogy.
Others Have tho Disease.
Further investigation showed that farm
ers who handle grain. millers who grind
It, men who thrash IT, and families which
use the straw IN beds or under carpets
are frequent sufferers from this form OF
skin malady. due in every instance where
careful investigation has been made not
10 'chiggers," but to the little predaciOus
parasite who finally attacks the human
species when his natural food disappears
Cattle and horses are also sometimes at
tackled.
The puncturng Of the skin by this
parasite is only uncomfortable. not dan
gerous. It can be avoided by the disuse