297 



Simple Tertian 



Examined during the commencement of 

 apyrexia, young parasites are found one-fifth to 

 one-ninth the size of the red cell. The corpuscles 

 may be slightly larger than normal. On the 

 following day the parasites occupy one-half to 

 two-thirds of the corpuscle, much pigmented^ but 

 not so actively motile as the smaller ones. The 

 red cells are much enlarged at the end of the 

 second day ; presegmenting forms are found. 

 Division into four to six or more parts may take 

 place six hours before an attack, but true fission 

 forms are only found two to three hours before an 

 attack. These forms have sixteen to twenty 

 spores ; so that, here again, the multiplication of a 

 group of parasites may be shown, microscopically, 

 to coincide with a febrile attack. But, as opposed 

 to quartan, the actual number of fission forms in 

 the peripheral circulation is small ; they are far 

 more numerous in the spleen. 



Double Tertian 



The interval between the development of the 

 two groups of parasites is about twenty-four 

 hours. So that if a blood examination be made 

 just before an attack, fission forms will be found, 

 and parasites about half- grown. Here again, by 

 following out the development periodically, these 

 latter forms will be found to sporulate on the next 

 day. 



Quartan Parasite 



If the blood be examined as soon as apyrexia 

 sets in, the corpuscles will contain j'oung parasites 



