l6o PLASMODIUM FALCIPARUM [CH. 



parasites will complete their cycle of schizogony every 72 hours 

 from this date onwards, i.e. on the fifth, eighth, eleventh days, etc. 

 The result of such a double infection will be the occurrence of 

 febrile attacks on two successive days followed by an interval 

 of one day, and to this type of fever the term Double Quartan 

 is applied. 



In the same way a patient may again become infected on 

 the only day on which schizogony is not taking place, and after 

 this last infection has developed will shew a rise in temperature 

 every day. This type of fever is known as Triple Quartan 

 Fever ; it may be distinguished from the other kinds of malaria 

 by the shape of the parasites. 



IIL Plasmodium falciparum (Welch, 1897) and Quotidian, 

 Malignant Tertian, or ^stivo-Autumnal Malaria. 



Synonyms : Oscillaria malaricB Laveran, 1881, pro parte. 

 Hcemamceba prcBcox Grassi and Feletti, 1890. Hcemamceha 

 malarice prcecox + H. malarice immaculatum Grassi and Feletti, 

 1890. Laverania malarice Grassi and Feletti, 1890. Plasmo- 

 dium malarice var. quoiidiance Celli and San Felice, 1890. 

 HcBmosporidium iindecimancB Lewkowicz, 1892. H. sedeci- 

 mance Lewkowicz, 1892. H. vigesimotertiancB Lewkowicz, 

 1892. Hcemamceba laverani Labbe, 1894. Hcsmatozoon falci- 

 parum Welch, 1897. Hcemamonas prcecox Ross, 1899. Plasmo- 

 dium malarice prcecox Labbe, 1899. Plasmodium prcecox 

 R. Blanchard, 1900. Hcetuamcrba malarice var. parva Laveran, 

 1900. Plasmodium immacidatum Schaudinn, 1902. Laverania 

 prcecox Nocard and Leclainche, 1903. 



Description. This is the smallest of the three species of 

 Plasmodium affecting man, the fully developed schizont being 

 not more than about 5^1 in diameter. The young sporozoite 

 is very small and, after penetrating a red cell, as a rule at once 

 assumes the ring form. The latter is characteristic in appear- 

 ance as the nucleus is always peripheral and the contours of 

 the ring are very dark and clear. The trophozoites have the 

 peculiarity of frequently appearing at the surface of the red cell. 

 They are distinguished from those of the other two species of 



