Evening star. [volume] (Washington, D.C.) 1854-1972, 1910-07-17

brown, some black and white, some yellow
or iridescent, gorgeous fellows, spotted and
streaked in all sorts of combinations. Some,
like the common marsh mosquito (Cnler
sOllicltanS), have striped legs. In size they
vary from tiny chaps an eighth of an inch
long to giants half an inch in length, such as
the far famed Jersey galinippers (Psoro
Phora cilidtd and Ps0robhora kO7oardii),
which are actually able to make an effective
puncture through a coat, waistcoat, and two
shirts (this on authority of Dr. John B.
Smith, State Entomologist of New Jersey!
A IL of this seems very curious; but in the
meantime those unfortunate wrigglers
have been waiting in the glass jar for some
thing to happen to them. They are lively
little fellows, and are getting ready to I'M
dergo remarkable transformation. After
changing their skin three times, they as
sumo, at the end of about two weeks, the
pupa form, looking to the naked eye more
like fat commas than anything else; and in
this stage they are comparatively inert,
floating at or close to the surface of the wa
ter, and lodging downward with absurd
jerks of their tails when disturbed.
When one of these pupa is examined un-
der the microscope, however, 1T IS seen to be
nothing more nor less than sort of case, in
which, for temporary purpose of Nature,
the adult mosquito is folded up and packed.
The observer can clearly distinguish the
eyes, the legs, and the wings of the full
1edged insect that is to be, the abdomen of
the latter being inclosed in the tail of the
pupa.
After two or three days spent in this pupa
case, the mosquito splits it open, and, using
the discarded skin as a little raft on which to
stand until its wings are dry, it then flies
away. Thus all the "skeets" evolved from
the wrigglers in the glass jar would make
their escape, if the receptacle was not kept
covered with piece of gauze, fastened with
a string or a rubber band AS it is, they are
captured one after another by the simple
expedient of poking the open end of a glass
test tube into the jar. Each insect, being
obliged by little manipulation to enter the
mouth of the test tube, flies upward to seek
the light, and is promptly imprisoned by
plug of raw cotton.
If the mosquitoes thus reared are wanted
merely for preservation as specimens, or for
examination with the microscope, it is easy
to kill them by exposing them to the fumes
of chloroform or cyanide of potash; but
they may be kept alive in suitable recepta-
cles or may even be transferred to homeo-
pathic walls and sent by post in mailing
tubes. Before mailing them, however, the
COttOn plugs III the Walls must De Qa1npened,
else they will dry up and die.
When, for the purpose of diagnosing
case of malaria, mosquitoes are used to obtain
samples of the patients blood, the insects
are afterward killed and their stomachs and
salivary glands examined under microscope
to find out if they contain any of the typical
malaria microbes, or zygotes. If microbes
appear, the character of the trouble is mani
fest.
But it is obvious that wild mosquitoes will
not serve, inasmuch as they are more or less
likely to be infected beforehand. The in
sects utilized in this way must be Matched
and reared in the laboratory to make sure
that they have never drunk blood. If they
have not, they cannot possibly be infected,
because it is only through this means that
they can get malaria. We are accustomed
to say that mosquitoes inoculate us with the
disease in question; but in reality we give
malaria to them.
For the purpose of malaria diagnosis, of
course, the Anopheles, or malaria mosquito,
and none other, must be employed, because
it alone is able to develop the zygotes. Ac-
cordingly, wild females of this genus must
be captured in the manner already described,
and induced to lay the wrigglers Matched
from the eggs being reared to the adult or
y,ir,oed form When thic hac baan accor,