Asexual Life Cycle 



5 2 9 



as the majority of writers believe, but it is an immaterial 

 difference, for the parasite soon makes clear that it is con- 

 suming the corpuscle. This little body is known as a 

 schizont. When stained with polychrome methylene-blue, 

 and examined under a high power of the microscope, it ap- 



Fig. 170. Plasmodium falciparum. Ookinetes in the stomach of An- 

 opheles (Grassi). 



pears as a little ring with a dark chromatin dot upon one 

 side. It grows steadily, feeding upon the hemoglobin, which 

 seems to be chemically transformed into fine or coarse gran- 

 ules of a bacillary or rounded form, presumably melanin. 

 In a length of time that varies 

 twenty-four to forty-eight hours 

 (Plasmodium falciparum), forty- 

 eight hours (Plasmodium vivax), 

 seventy-two hours (Plasmodium 

 malariae) the schizonts mature, 

 becoming nearly as large or quite 

 as large as the corpuscles. The 

 pigment granules now collect at 

 the center and the substance of 

 the parasite divides into a group 

 of equal-sized merozoits, com- 

 monly known as spores. Of these cipafum. Transverse section 

 there are usually eight in the J the stomach of Anopheles, 

 ,, f *r*t ,. showing the ookmetes of the 



meroblasts of Plasmodium ma- parasite in various stages of 

 lariae, from fifteen to twenty-five development attached to the 

 in those of Plasmodium vivax, outer surf ace (Grassi) . 

 and from eight to twenty-five 



in Plasmodium falciparum. As the spores become fully 

 formed and ready to separate, the paroxysm of the disease 

 begins. It ends as the spores are freed and enter new 

 corpuscles to begin the cycle over again. After a good many 

 34 



Fig. 171. Plasmodium fal- 



