from
The Collaborative International Dictionary of English v.0.48
Malaria parasite \Malaria parasite\
Any of several minute protozoans of the genus {Plasmodium}
(syn. {Haematozoon}) which in their adult condition live in
the tissues of mosquitoes of the genus {Anopheles} (which
see) and when transferred to the blood of man, by the bite of
the mosquito, produce malaria.
Note: The young parasites, or sporozoites, enter the red
blood corpuscles, growing at their expense, undergoing
sporulation, and finally destroying the corpuscles,
thus liberating in the blood plasma an immense number
of small spores called merozoites. An indefinite but
not ultimated number of such generations may follow,
but if meanwhile the host is bitten by a mosquito, the
parasites develop into gametes in the stomach of the
insect. These conjugate, the zygote thus produced
divides, forming spores, and eventually sporozoites,
which, penetrating to the salivary glands of the
mosquito, may be introduced into a new host. The
attacks of the disease coincide with the dissolution of
the corpuscles and liberation of the spores and
products of growth of the parasites into the blood
plasma. Several species of the parasite are
distinguished, as {Plasmodium vivax}, producing tertian
malaria; {Plasmodium malariae}, quartan malaria; and
{Plasmodium (subgenus Laverania) falciferum}, the
malarial fever of summer and autumn common in the
tropics.
[Webster 1913 Suppl.]