1 66 



THE ANIMAL PARASITES OF MAN 



The chief distinctive characteristics of the simple tertian parasite, 

 as seen in infected blood, are : (i) The infected red-cell is usually 

 enlarged ; (2) the presence of fine red granules known as Schuffner's 

 dots in the red blood corpuscles, after Romanowsky staining ; (3) 

 the fragile appearance of the parasite compared with other species. 

 Large forms are pigmented, irregular and " flimsy-looking," some- 

 times appearing to consist of separate parts. Irregularity of contour 

 is common. 



Ahmed Emin 1 (1914) has described a small variety of P. vivax. 



Plasmodium malariae, Laveran. 



Syn. : Oscillaria malaria, Laveran, p.p., 1883 ; Hcemamceba malaria, Gr. et Fel., 

 1890; Plasmodium malaria var. quartana, Celli et Sanfel., 1891 ; Hamamceba 

 laverani var. quartana Labbe, 1894 ; Hamosporidium quartana, Lewkovvitz, 1897 ; 

 Plasmodium malaria quartanum, Labbe, 1899 ; Plasmodium golgii, Sambon, 1902 ; 

 Laverania malaria, Jancso, 1905 nee Grass! et Fel. 1890 ; Hamamceba malaria 

 var. quartana ; Lav., 1901. 



Plasmodium malarice is the parasite of quartan malaria (fig. 86). 

 The trophozoites of the quartan parasite differ from the corresponding 

 stages of the tertian parasite in that their motility is less and soon 

 ceases. They differ also in their slower growth, by the early 

 disappearance of the food vacuole, by the more marked formation 

 of the dark brown pigment, and by the fact that the red blood 

 corpuscles attacked are not altered either in colour or size. 



FIG. 86. Development of the quartan parasite in the red corpuscles of man asexual 

 stages. (After Manson.) 



When the parasites have grown almost to the size of the erythrocytes 

 schizogony occurs. The pigment granules arrange themselves in lines 

 radiating towards the centre and the merozoites are also radially 

 disposed in groups of 6, 8, 10 or even 12, but are often arranged 

 less regularly. The whole development, growth and schizogony, 

 occupies seventy-two hours. 



1 Bull. Soc. Path. Exot. t vii, p. 385. 



