The Republican. [volume] (Oakland, Md.) 1877-current, 1924-08-21
DESCRIBES WORK
OF DEADLY PEST
u. S. Bureau Reports on
Mosquito Experiments.

GU CLdlCS, anu Will us
for all future time Is most unlikely,
yet the so-called ydloEfever mosquito
is perhaps the commonest household
! mosquito in the Gulf states, and it has
been shown to be responsible for the
carriage of dengue or so-called back
bone fever. AS it is distinctly a house
hold mosquito which Is readily con-
trolled the importance of such con-
troll is obvious.
''The only species of mosquito" says
L. o. Howard, chief Of the bureau of
entomology, United States Department
of Agriculture, in a bulletin on the
| subject, (which has been shown to
| transmit yellow fever is a small form
well known in the tropics. 1t Is some
what variable in size, but on the whole
| is so small as to require a mosquito bar
J of twenty strands, or nineteen meshes,
to the inch to prevent its entrance in
to screened rooms. Both males and
females can pass through netting
containing sixteen strands or nineteen
Ineshes, TO the inch. 1t Is strikingly
| marked, and, on the whole, when seen
| under the lens, beautiful insect. Its
| general color is dark. but its thoraX
is marked with a silvery white, and
there Is q Silvery white spot on each
side of the abdomen segments. The
| legs are banded alternately with black
and pure white, and the long palpi of
| the male are also alternately banded
with black and pure white.
"The yellow-feveP mosquito is insep-
arably associated with man In the
tropics. 1t is essentially a town mos
quito, and normally If is never found
| at a great distance from habitatiOns. 1t
shows very decided preference for
human blood, and it must have blood
| for the development of its legs. Both
sexes inhabit houses and when there is
| a supply of water the entire life cycle
takes place indoors.
Knows the Ways of Man.
ats long association with man Is
shown by many of It's habits. 1t ap-
| proaches stealthily from behind. It re-
treats upon the slightest alarm. The
ankles and, when one is sitting at a
table or desk, the underside of the
| hands and wrists are favorite points
of attack 1t attacks silently, whereas
other mosquitoes have a piping or hum
ming note The warning sound has
doubtless been suppressed in the eyo-
lutionary process of its adaptation to
man.
| "The female sucks blood when it Is
available, and needs blood to develop
! her eggs. In captivity she has been
| kept alive for long time on honey
! or other sweet substance. She is at
| tracted to portions of the body COW
| cred with perspiration. A female will
! bite within eighteen to twenty-four
hours after she energies from the pupa.
| Virgin females will bite but fortified
females are more greedy. After a meal
of blood she is very sluggish; she flies
with difficulty, seeking a hiding place
| for digestion. Several hours are con-
sumed in digestion, and then the fe-
male is anxious for another meal of
! blood. The species normally suck
blood repeatedly. In thirty-One days
| female is recorded to have sucked
blood twelve times. By biting a num-
Der of different individuals the chances
! of becoming herself infected with yell
low fever and transmitting the dis
eases are greatly increased.
Mosquito Prefers Man.
1.-THE yellow-fever mosquito can sub
sist upon the blood of any warm
blooded animal. but shows a decided
| preference for man. 1t prefers the
white race to dark races, and among
the whites attacks by preference
young, vigorous persons Of fine skin
and good color rather than anemic
or aged people. 1t will also feed upon
birds, and 1t has been carried alive
from Brazil TO Europe by being fed
upon canary birds, Instances are on
record Of the biting of corpses.
"The popular name in the British
West Indies, day mosquito, is derived
from the fact that this species is usual
ly active and bites only in the day
time, although, where there is light
in the room, it may also bite at night
adult females have been kept alive
for long periods by feeding them upon
bananas and other fruit, upon honey,
molasses and other sweet substances
Beyond the fortieth day the mortality
becomes great. They will live longer
when the atmosphere Is moist. Cult
eras, in Cuba, kept five infected adult
females alive for 101 days and enc
for 154 days.
"The cessation Of former yellOw-fe-
yer epidemics in the southern United
States on the appearance of the first
cold weather in November and De-
cember was due to the fact that the
yellow-fever mosquito is killed by the
cold.
"The yellOwfever mosquito is
strong flier; nevertheless, it does not
fly very far and, as has already been
pointed out is rarely found away from
houses 1t apparently never flies very
high and is found by preference
in the lower stories Of houses. There
is conflicting evidence regarding the
effect of strong currents of wind on
this species, and 1t is recorded that
strong air currents produced by me-