1922] on Microscopic Parasites and their Carriers 509 



Fig. 3.— Plasmodium falciparum, the malignant 

 Tertian Malarial Parasite of Man, and its development in 

 the anopheline mosquito. 



a-d The parasites in the red blood corpuscles of man. (Magnified 3000 times.) 



a, young ring form ; b, adult multiplying form ; c and d, female and male 

 crescent forms (gametocytes), which can only develop further in the 

 mosquito. 



p, s, l, k, h Diagram of development in the mosquito. 



h, development in the lumen of the stomach ; k, development on the outer 

 surface of the stomach ; l, sporozoites escaping from cyst and making 

 their way towards the salivary glands ; s, salivary glands containing 

 sporozoites; p, proboscis, which inflicts the wound and through which 

 the saliva containing sporozoites is injected. 



w-z Details of the development of the cysts on the stomach of the 

 mosquito as shown at k. (Magnified 400 times.) 



