PROTOZOA 



39 



...e 



-« 



thousands of tiny sporozoites which collect in the mosquito's 

 salivary glands. If the mosquito afterwards bites a human being 

 some of the sporozoites from the wound may be introduced and will 

 enter the red blood corpuscles, and when sufficiently numerous will 

 produce a chill. Such chills occur at the end of every 48 hours with 

 each recurring cycle of sporulation, in the case of Plasmodium vivax. 

 Quinine, the specific against malaria, may be resisted by certain 

 of the malarial parasites in the spleen or bone marrow. 



Orders of Sporozoa. Order i. Gregarinida. — 

 Monocystis is an abundant parasite of the seminal 

 vesicles of the earthworm. Porospora gigantea (two- 

 thirds of an inch long) is parasitic in the alimentary 

 tube of the lobster. 



Order 2. Coccidia. — Coccidia cause red dysentery 

 in calves and infest the liver and intestine of man 

 and other vertebrates, besides oysters, insects and 

 Crustacea. At least five species of Eimeria occur in 

 chickens. One of these is very destructive to young 

 chickens. 



Order ?. — Haemosporidia live in the blood. The 



r -I- 1 T-»I J- J J U tic. 17. A 



two important families are the Flasmodidae and the poiycystid 



Babesidae. gregarine. 



The Plasmodidae include the malaria organisms. Wasielewsky. 



They induce malaria in birds and mammals. Plus- (From Calk- 



modium vivax causes tertian fever, P. malariae causes ":^' '° °^/ 



• 1 r of the rroto- 



quartan fever and P. falciparum causes tropical tever. .^^ Courtesy 



Paresis has recently been treated successfully by of Lea and 



infecting the patients with malaria. The organisms Febiger.) 



are transmitted by Anopheline mosquitoes. (See Fig. 



89.) O'Roke (1930) has found a fatal malarial disease in quails 



transmitted by a degenerate fly, Lynchia, living in the feathers. 



The Babesidae include several important blood parasites, all of 



which are transmitted by ticks. Babesia bigemina, the organism 



producing Texas cattle fever, is transmitted by the bite of the tick 



Boophilus annulatus. Death occurs in acute cases in two days. 



Trypan-blue has been used in the treatment of babesiasis. Babesia 



canis, the organism attacking dogs, has been the most studied. 



East Coast fever is caused by Babesia parva which is found in the red 



blood corpuscles of cattle, producing anemia. Oroya fever is a 



human disease occurring in mountain valleys of Peru. It is a 



