Source : Webster's Revised Unabridged Dictionary (1913)

Malaria parasite \Malaria parasite\
   Any of several minute protozoans of the genus {Plasmodium}
   (syn. {H[ae]matozo["o]n}) 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 {P. vivax}, producing tertian
         malaria; {P. malari[ae]}, quartan malaria; and {P.
         (subgenus Laverania) falciferum}, the malarial fever of
         summer and autumn common in the tropics.