. Public health and preventive medicine. long pseudopodia, and growing at the expense of the haemoglobin. Tt absorbs andbreaks up the red colouring matter, so that, if viewed at thisstage through the microscope, itappears as a pale, somewhatindefinite, protoplasmic disc occu-pying more or less space withinthe rim of the corpuscle. Scattered through this pale area, are the blackpigment grains of melanin derived from the disintegrated haemoglobin. The larger the plasmodium grows, the more sluggish is its movement, tdlfinally all motion ceases, but not till the pigment particles have undergonemor
. Public health and preventive medicine. long pseudopodia, and growing at the expense of the haemoglobin. Tt absorbs andbreaks up the red colouring matter, so that, if viewed at thisstage through the microscope, itappears as a pale, somewhatindefinite, protoplasmic disc occu-pying more or less space withinthe rim of the corpuscle. Scattered through this pale area, are the blackpigment grains of melanin derived from the disintegrated haemoglobin. The larger the plasmodium grows, the more sluggish is its movement, tdlfinally all motion ceases, but not till the pigment particles have undergonemore or less central aggregation and the pale protoplasm has arranged itselfround the resulting masses in segments (spores), each somewhat similar to theform which characterised the plasmodium on its entrance into the humancirculation from the mosquito, the whole arrangement being known as body (Plate V. Fig. 1). This is the sporocyte. The red bloodcorpuscle now breaks down, and the segments or spores fall apart, and with the 4. itiou of malarial parasites in the nios-6, Stages of the gametocyte (fromcrescent to flagellated body), c, Macrogamete, entrance of flagellum. d, Stomach amisalivary gland of mosquito, showing differentstages of the zygotes passing through wall ofstomach, e, Zygotes at different ages. /, Rup-ture of zygote capsule and escape of sporozoites. 50 MEDICINE pigment are set free in the liquor sanguinis. Phagocytosis now takes place,the pigment and many of the spores being absorbed by the leucocytes, and sopassing out of tins cycle. The remainder of the spores become attached tofresh red blood corpuscles, which they enter, and the cycle of events describedabove recurs. The enormous destruction of red blood corpuscles resulting from therepetition of this process at once explains the anaemia which accompaniesmalarial fever. Having thus briefly considered the mosquito-man cycle of aPlasmodium, we are in a position to describe the various forms in
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