72 MOSQUITOES AND MALARIA. 



4. The blood corpuscle breaks up and the spores enter 

 the liquor sanguinis ; 



5. Such spores as escape the phagocytes attq,ch themselves 

 to red corpuscles and enter thein ; 



G. In the interior of the corpuscle the plasmodium exhibits 

 Amoeboid movements, and grows at the expense of the 

 hfpmoglobin ; 



7. By assimilation they convert the haemoglobin into the 

 pale substance of the plasmodium and into melanin ; 



8. Finally, just before sporulation all motion ceases. 



STRUCTURE. 



On staining, the plasmodial spore is found to consist of a 

 minute, deeply tinted nucleolus, surrounded by an unstained 

 vesicular nucleus,' and this again by a covering of protoplasm. 

 As the parasite grows and approaches maturity the nucleolus 

 disperses, and the vesicular nucleus becomes less distinct, finally 

 just before sporulation both nucleus and nucleolus cease to be 

 distinguishable. 



MELANIN'. 



The melanin particles occur either in dust-like specks, in 

 coarse grains, in short rods, or aggregated into dense clumps. 



LATENT PHASE. 



Concurrently with the subsidence of acute clinical symptoms, 

 the Plasmodium may disappear from the general circulation and 

 pass into a latent stage. This it does either spontaneously 

 or as the result of the action of quinine. The exact conditions 

 which cause latency are not known. 



EXTRA CORPOREAL CYCLE FLAGELLATED BODIES. 



When fresh malarial blood is examined under the micro- 

 scope, strange octopus-like creatures, the flagellated bodies 

 appear ; like the ordinary parasite they are of colourless proto- 

 plasm, with melanin granules, but they are furnished with one 

 to six whip-like arms, termed flagella. These arms, three or 

 four times as long as a blood corpuscle is broad, move with the 

 greatest rapidity, and they double up and distort the blood 

 corpuscles by their blows. Occasionally the flagella break away 

 and swim about freely. 



Careful observation shows that the flagellated bodies are 

 developed from two forms of the extra-corpuscular parasite — in 



