ANIMAL PARASITES 



87 



cles are not enlarged and the number of merozoites produced 

 from a single schizont varies from 6 to 12. Specimens will 

 be demonstrated if available. 



Bird Malaria. — Several species of our native birds harbor 

 malarial parasites (Fig. 28) which belong to the same genus, 

 Plasmodium, as do those of man. The better known of these 

 complete their asexual cycle in 24 hours. The gametocytes 

 differ from the schizonts much as in the species affecting man. 



Fig. 



S & 7 



28/ — Malarial parasites from English sparrow. 1, microgametocyte of 



Plasmodium prcecox; 2, macrogametocyte of same; 3-5, stages in the asexual 

 development; 6, microgametocyte of Plasmodium inconstans; 7, macrogametocyte 

 of same. (After Hartman.) 



Study the demonstration specimens, making drawings of typical 

 stages. 



The sexual cycle of the malarial parasites is not readily studied 

 in an introductory course. Such stages as are available will be 

 demonstrated. They are most readily obtained in the case of 

 the bird malarias which undergo their development in a number 

 of species of mosquitoes, including Culex pipiens, the common 

 rain-barrel species. 



Piroplasmidffi. — These are minute hsemosporidians which, 

 like the malarial parasites, inhabit the red blood corpuscles of 



