299. 



During the apyrexia, forms one-fourth to one- 

 third of a red cell are found, and the parasites are 

 found in greatest numbers. Fission and preseg- 

 menting forms are extremely rare in the tropics. 

 During the next attack the young forms are again 

 found, and so the time of the cycle, as we have 

 shown above, may be deduced, and may be con- 

 trolled by observation of intermediate stages. 



Quotidian 



Parasites have been described which com- 

 plete their development in twenty-four hours 

 (about). Thus, at the pyrexia young forms occur. 

 During the apyretic interval large forms and pre- 

 segmenting forms, and, again, at the next attack 

 young forms, thus developing in twenty-four hours. 

 As we have stated above, to establish accurately this 

 cycle three periods would have to be traced : — 



No. I. (? Twelve hours) from young forms 

 to largest forms. 



No. 2. (? Twelve hours) from largest forms 

 to young forms. 



No. 3. Twenty-four hours from young forms 

 to young forms. 



While some consider that the quotidian tem- 

 perature is due to the fact that the malignant 

 tertian has a very variable period of development, 

 viz., twenty-four to forty-eight hours, and, in fact, 

 all intermediate times, others consider that with 

 one generation of parasites there is a second 

 accumulation of young forms in sufficient quantity 

 to produce a quotidian attack. 



In quotidian fever, due to the malignant 

 tertian parasite, the characteristic febrile attack, 



