The Washington herald., 1913-07-27

Have you come across any yellow fever
mosquitoes in the near neighborhood of
your domicile lately?
Not SO far as you knoy, presumably.
And yet this may have happened, and II
is even possible that members OF your
family have been bitten by them.
Such a thing seems scarce credible.
Nevertheless, the government Bureau OF
Entomology is about to come out with
the startling statement that almost every
summer yellow fever mosquitoes are car
ried in railroad cars, on through trains.
to Philadelphia, New York, and Chicago.
The fact is beyond question, for they
have been captured on these trains and
their species identified.
Not only do they journey to the North
in summer, in the manner described, but
they breed there. They are tropical in
sects, but the climate Of our northern
cities suits them first-rate during the
warm season. In 1904, they were found
breeding abundantly on the grounds of
or more persons suffering from incipient
yellow fever CHANGED to come to the fair,
he mosquitoes might have derived from
then the infection and spread 1t in an
alarming epidemic.
one should realize, Of course. that the
yellow fever mosquito does not carry the
disease unless it has happened to become
infected by biting a person suffering
from the malady. But, as we now know,
mosquitoes thus infected did in earlier
uays find their way to the north in trad
ing -vessels-most commonly from Vera
Cruz, the yellow fever port par excel
Icnce-and spread destructive epidemics
in Philadelphia. and other cities, even 6
far as Montreal.
Common in the Tropics.
This species Of mosquito is very COM
mon in the tropics, where 1t seems to be
.Eseparably associated with man, never
found at a great distance from human
habitations. il is essentially a town IL
sect, and inhabits houses. when there
is water accessible for the purpose in
doors in a pitcher or other receptacle, 1t
breeds there. Strikingiy marked. 1t is
a beautiful creature when seen under
the microscope, with a silvery white
lyre-shaped pattern on the thorax. and
white stripes on the abdomen. The legs
are banded with black and white.
In the West Indies 1t is known as the
house mosquito" or day mosquito. :"
because 1t flies in the day time. So small
is it in size that ordinary wire screens
or bars will not keep 1t out 1t Ii ex-
tremely wary, approaching the intended
NlCIln Sl6dlluuy pcuAuus dilu ilS
attack is silent-that Is to say, without
the usual warning Of a piping or hum
ming note. These habits doubtless arise
from long intimacy with man.
The yellow fever mosquito has Q Gu.
Tious way Of hiding. 1t conceals itself in
garments, working its way into pockets
and uLder the lapels OF coats, or crawling
up under the trousers or skirts to bite
the legs. In houses it will hide In dark
.vnl ~
hind the heads Of old-fashioned bed.
steads. It will even enter closets and
seek concealment in the folds Of clothing
hanging there.
This pestiferous insect il q permanent
resident along the Gulf Coast. But, as
already explained, 1t is harmless enough,
save for the annoyance It infiicts, when
not infected. Epidemics Of yellow fever
arise only when II has had an opportu-
nifty to bite sufferers from the disease.
and thereupon to distribute the germs
of the latter by attacking other people.
This is SO well understood nowadays that
the first thing done with yellow fever
patient is to isolate him in such q way,
with suitable protection by screens and
bars, that mosquitoes shall not be able
to get at him. Thanks to this simple
piece of knowledge. we are never likely
to have another serious epidemic Of the
malady in this country.
Sensitive to Cold.
The species Is very sensitive to cold,
being quickly killed by frost. But In
the summer time 1t is widely spread by
the railroads, and by other means Incl
dental to commerce, occupying and
breeding in regions where It could not
possibly survive the winter. In mid
summer (say the government entomolo-
gists) 1t is found almost everywhere In
the Southern States. and IL liable to
make its way to Northern cities, multi
plying there in large numberk
Thus it may be said that the region
At permanent distribution Of this mos.