The evening times., 1900-07-14

BAL1lMOfNE, Jull l1--oSles-tiSl5 iOI
years have been studying the disease
germs taken by mosquitoes from one hu-
man being. developed in the body of the
insect. and then injected into another per-
son to poison his blood with malaria. but
few have given much attention to the
study OF the poison generated by the mos
quito itself and injected into the victim OF
his. or rather her. bite. The effects Of this
poisoa are apparent every day in the
bIot hes. and sometimes slight ulcerations,
which surround the scene OF the mOsqui-
! tos blood-sucking visit.
Dr. W. S. Thayer. who at Johns Hopkins
Hospital is engaged in a series of expert
ments which carry out the now accepted
theory that mosquitoes transmit malaria.
said yesterday that he knew Of no scientific
investigation Of the mosquito poison which
accompanie, every bite inflicted by the in
sect So widespread are the raYages OF the
mosquito ,hat nearly everyone is acQuaint-
ed by personal contact with the contents OF
the poison gland OF the lille insect with
the bite comes a stInging sensation OF
greater or less intensity. according to the
! susceptibility OF the person suffering II.
Itching follows, which is usually aIlayed by
scratching the bite Here is where the
damage is done. according 10 some phys
clans. From the scratching hnger-n
germs get into the slight wound and these
set up an irritation and local Inflammation
which may result in the formation OF a
little pUstuie
Il Is believed that the actual poison of
the mosquito which is really its saliva is
snly a slightly Irritating organic poison
4 = aH1kw
human system. its irritating influence soon
wearing away. But the fnger-nau does
the work by introducing germs into the
| tiny vound. SO minute are the litie poison
glands and so small is the amount Of poi
| son secreted By the insect that no one has
| taken the trouble to gather II in quantity
/ sufficient for chemical analysis
The function Of the musquito's poison is
/ probably two-fold. Some observers think
/ il Is injected 10 aid in lUbIicating the pro-
I boscis as IL is inserted In the skin to Sc
| cure the Insects meal oE blood Another
\ theory is that tie poisonous saliva serves
/ 10 make more fluid blood. so that II may
be more easily sucked out by the mosquito
/ This seems 20 be borne out BY the noted
1 absCeHce Of irritation from the poison il
/ the mosquito Is allowed 10 suck his I'll.
as then the poison IS probably sucked out
1 also II the mosquito IS Interrupted in its
uA.
Or. John 5 Fulton. Secretary Of the State
Board Of Health. says that when living in
= mosquito injected section Of Maryland be
tried not 10 mind the little pests. allowing
them 10 have their fessts of his blood un-
distured. Soon. he says. he became i'm
mUne 10 the poison ana no longer minded
| he bites Ror vas he Inconvenience by the
| Dulctuves Of the mosquitoes
While people are rising in their wrath
D -
| the pestiferOus mosquitoes that are an
/ aoying them f. their homes and yards they
may be interested 10 know just what they
are shifting would Ike 10 smite In the
| 6Tst place ii is the female OF the species
/ that has the bloodthirstyl propensity
The taste Tor blood rs supposed to be
I largely ascquired for !, would obviously be
| impossible Tor all mosquitoes 10 feed or
warm biOoded animals Their regular diet
I IS a vegetable ore-iuiees sucked from
| fruits ard flowers Some species have
! been studied which viii keep up their veg
etabie habits. or other species the fe-
males alone are block suckers while the
! males stick 20 their Vegetable DIET. In
rare eases species have been found in
which both sexes prey on the blood OF an
imaIs.
The act OF biting OF = mosquito has been
I likened 10 the sinking Of an artesian vel
I sha.F. Its biting apparatus is the protOs-
els, which has been discussed into nine
parts One OF its principal parts is the
! upper lip. which extends nearly 10 the e. d
OF the organ Beneath il and in a groove
Is long pointed cacu,a which IS a So-t o.
extension OF the phcrarEeal tube Through
this the blood is sucked On either S de
are two lancet-shsped pieces. mandib.es
aDG maxillae. which prepare the wax for
| the assertion OF the probOsciS- The snaui!-
Tafs 10 ard Fs4.,l
eE,is with a number OF spine-like oarbs
probably TO enable the mosquito TO hold
on after il has once started on its quest
for blood. Beneath all is a sheath which
inclOses the other parts except along It's
upper border when open. This is the low
er liD. and IS somewhat dilated at its end
int pair OF pointed valves. These prob
ably have 10 do with the sucking of blood
When the probOscis is in action il is Ill
forced Into the skin except the Shsath
which is bent into a sort OF loop. which
becomes narrower as The piercing organ
peneEstes more deeply. At either side OF
the base OF the proboscis is a pair OF
lointed appendages, msxillary palpi. The
poison is secreted either in two glands
which are situated at each side OF the
thorax- or in q single gland at the base o.
The proboscIs-
The sides ard front Of the head OF the
mosquito are occupied by facetted eyes
This probably accounts for the ease with
which mosquitoes escape from impending
smashing under an Upliftei hand They
are able to see ali around then, and so are
able to get out OF danger. In some spa.ies
tie eyes touch cach other in front, go COM
pletely do they cover the head.
A recent work on gnats or mosquitoes.
by Major George NJ. Giles. an English in
Testigator, names over 240 distinct spe-
cies- or these the culeX varieties comprise
about three-fourths. These are distfn-
guished from the anopheles. or malaria
bearing mosquitoes. With the exception of
the polar regions II is said that no at all
extensive land surface on the globe is free
from mosquitoes In North America there
are no less than forty-one culex species.
As rule the culex is so5erly colared
although under the lens he shows elaborate
ard beautiful marking Most OF them have
no definite spots on the wings. as distin-
guiShed from the mottled- winged anophe-
les Such distinctions CT the culex varie-
ties are noted as varying coIors Of thorax
and abdomen and knees spotted. The
males are distinguished by having plurned
anteEnae. while the females have their an
tenEae nearly bare. or with tufts OF hair
al the base.
Probably the most common culex mos
quito Of this locality is the culex signhier.
which is thus described
Wings unspOtted. but with brindle
scales. tarsal joints banded. white az both
ends. thoTax bTownish black, with two sub
dOrsal siivery vitae. on the anterior half
and arcuate silyery lines throughout Alb
Gonen yic.aceous with white basal bands
70 the segments."
III.