MALARIA 



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vessels of the deeper viscera. Its flagellated phase is 

 developed from ' crescents.' 



(d) Malignant Quotidian.— The cycle of development of 

 this variety takes twenty-four hours. The parasite is 

 always small, even in the adult state, and frequently 

 assumes the ' ring ' form in the corpuscle. The spores are 

 generally formed by irregular segmentation. The flagellated 

 phase is formed from crescents. This and the preceding 

 produce fevers of a more or less irregular type. 



Irregular types of fever may be produced by different 

 generations of the same parasite, or by different varieties, 

 resulting in mixed infections. It is quite possible, when 

 the nature of the various tropical fevers has been more 

 fully investigated, that other varieties of the parasite will 

 be discovered. 



According to various authors, there are five distinct 

 forms of malarial parasite : quartan, benign tertian, malign 

 tertian, pigmented quotidian and non-pigmented quotidian, 

 whose characters may be arranged as follows : 



