The Prince George's enquirer and southern Maryland advertiser. (Upper Marlborough, Md.) 1882-1925, 1899-05-05
k0IXAL 81! 4! s:*;:s s:*":&
Makes the food more delicious and wholesome
ABSOLUTELY PURE


certain length OF time after feeding.
curious large pigmcntcd bodies began
to appear in the walls of the mosuui-
tos stomach. The pigment Of these
elements was clearly derived from that
within the parasites which had been
taken into the body of the mosquito.
These structures which appeared in
crops after every feeding of the mos
quito upon infected blood, were OBJ
served to increase gradually in size,
until finally, at the end Of six days,
they reached very considerable diam
eter, nearly ten times that of red
blood corpuscle. At this time, accord
ing to Ross, they protrnde from the
walls of the stomach into the body
cavity of the mosquito. In some full
! grown forms a-curious radial station
was noted.
I Later Ross found that in cases
where the large elements had ruptured,
the body cavity contained great num-
bers of small spindle-shaped, rather
tlattened structures which he was able
| to prove, had escaped at the time rup-
ture of the mother body; to these fila
ments was due the striatcd appearance
above noted. After their escape from
!
| the mother body, they circulate in the
| insects blood. Ross also discovered
the presence of two glands in the tho
raN of the mosquito, which consist of
Il number of plump cells arranged
about ducts, which finally unite, FORM
ing common trunk opening into the
probosis-salivary glands, which pro-
badly convey the poison of the insect.
/ In he cells of these glands numbers
Of the tilamentous bodies become accu-
mulated; Suspecting that it might be
by means of these structures that the
infection was carried from the mos
| quito to bird, he exposed healthy birds
to the bites of insects which had been
fed upon infected brns at period
such that the filamentous bodies must
be present in the salivary glands. The
experiment was brilliantly successful.
Ross was able in almost every in
stance to produce an infection consi-
! derably more severe than was the rule
in birds where the source of the infec-
ton was unknown. Indeed, some of
the birds died of the discase-an unu-
sual result
II then Ross observations are accu-
rate, we have ut last the demonstra-
tion that parasite closely similar to
the malarial organism in man may
have two cycles of eXistence-one
within its warm blooded human host,
and one taking. place within the body
Of the mosquito which serves as an in
termedate host, being capable later of
actually transmitting the disease from
infected to non-nfected individuals.
And when we follow these observa-
tions step by step, we cannot fail to be
led to believe that the first stage in the
process is formulation as observed by
MacCallun. Ross has not, as yet, re-
ported the manner of entrance Of the
parasites into the stomach wall of the
mosquito but when we remember the
extraordinary behavior the pseudo
vcrmicule which arises from the fecun-
dated parasite-its sharp point, and
the manner in which it is capable of
piercing and destroying everything in
| its way-it would seem almost more
| than probable that it is in this stage
/ that penetration Of the intestinal wall
takes place.
Not the least interesting point
brought forth by these observations is
the suggestion that a patient infected
with malaria may be through the help
Of the mosquito a source of contagion
! to those about him.
s".s
! have already spoken of the fact
/ that three distinct varieties Of the ma
larial parasite have been described. 1t
/ is interesting to note that these three
/ varieties are each III turn associated
! with 4 definite type of fever. The
/ quartan parasite, it will be remember
/ ed has cycle of existence lasting
/ about scvcntv-two hours, and further
| possesses the remarkable charactcris-
tic that it is present in the blood of in
! ftctcl individuals in great groups, all
/ the members of which are approXi-
matcly at the same stage of develop
mcnt Thus, in infections with a sim
/ gle group of organisms, speculation
occurs at intervals of scvcnty>two
hours of every fourth day.
1t has been shown that the paroN-
vsm in malarial fever is always asso-
ciatcd with the speculation of 4 group
Of parasites, so that in such an intec-
ton the chill occurs every fourth day.
! There is reason to believe that the i'm
mediate cause of the paroXysm is some
poisonous substance set free by the
parasites at the time of their sporula
J tirn.