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GENERAL ZOOLOGY 



In its simplest form the animal resembles an extremely 

 small amoeba. In that stage it is found in the red corpuscles 

 of human blood. There the parasite increases in size until it 



Mosquito 



USfc.. 



Fig. 155. Stages in the development of the parasite which causes malaria 



Stages a to e occur in the human blood. The parasite lives in the red blood cor- 

 puscles, (a to d). When blood from a malarial patient is taken into the body of a 

 mosquito the spores develop into germ cells (h and i). After fertilization (j), the 

 parasite enters the tissues of the mosquito (I) and multiplies rapidly (m and n), 

 forming myriads of small spores (o) ready to infect other human beings when the 

 mosquito bites them, p shows the stomach of a mosquito with swellings pro- 

 duced by the parasite. (After Gruenberg) 



almost fills the corpuscle (Fig. 155, c) ; then it divides into 

 small bodies called spores (Fig. 155, d). The process of 

 spore formation causes the chill that accompanies malaria. 

 When the spores burst from their spore cases (Fig. 155, e) 



