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A MANUAL OF BACTERIOLOGY 



(3) The cestivo-autumnal, malignant, pernicious, or sub- 

 tertian, fevers (Fig. 63). This is a common form of 

 malaria. This parasite (Laverania malarice, P. falci- 

 parum) (or parasites, for it has been divided into three 

 species by the Italian observers, viz. the pigmented 

 (L. prcecox) and the unpigmented (L. immaculata) quo- 

 tidian and the malignant tertian, but this is not generally 

 accepted) is much smaller than the quartan or benign 

 tertian, and when it reaches the stage of multiplication it 

 disappears from the peripheral blood and collects in the 



FIG. 63. The sub-tertian parasite : a, b, c, amcebulae ; d, sporocyte ; 

 e, free spores ; /, g, h, female gametocyte ; j, k, I, male gametocyte. 

 (After Rees.) 



internal organs, spleen, liver, cerebral capillaries, and 

 bone-marrow. It is actively amoeboid, seems to change 

 its position within the corpuscle, and the pigment- 

 granules are very fine in the young parasites, but early 

 aggregate into large clumps. The fission forms (d, e) are 

 met with only in the internal organs. Multiple infection 

 of the corpuscles may also occur. The corpuscles often 

 suffer severely from the infection, some being shrivelled 

 and spinous, others dark in colour, " brassy " ; they may 

 also be altered or destroyed without being actually 

 invaded by the parasite. It is in this form that the 

 crescentic bodies appear (/, j, and Plate XXIX, b). These, 



