426 



SPECIFIC MICRO-ORGANISMS 



by recurrent paroxysms of fever with afebrile intervals, progress- 

 ive anemia and weakness, with the accumulation of a dark brown 

 or black pigment in the spleen and liver. This pigment is pro- 

 duced by the parasites and set free into the blood when they 



FIG. 202. Plasmodium malaria. Stages of the asexual cycle in the circulating 

 blood. Note the absence of granulation from the hemoglobin and the uniform size 

 of the red blood cells. X22oo. (After Do flein.) 



segment. The estivo-autumnal malaria caused by PL falci- 

 parum shows a somewhat irregular and not very characteristic 

 fever curve, but usually there is fever every day (quotidian fe- 

 ver). The tertian fever due to infection with PL vivax is char- 



FIG. 203. Plasmodium malaria. Sexual cells in the circulating blood. A , Young 

 gametocyte. B, Full-grown macrogametocyte. C, Full-grown microgametocyte. 

 X 2 200. (After Do flein.} 



acterized by febrile attacks recurring at intervals of 48 hours and 

 bearing a very definite relation to the asexual cycle of the para- 

 site. The segmentation of the plasmodium is coincident with 

 the chill and the rise in the patient's temperature. In quartan 





