Mosquitoes and Malaria 109 



It is interesting, too, to note in this connection that it 

 was another French surgeon who in 1840 discovered 

 that sulphate of quinine is a specific for malaria. 



The next important step was made in 1885 by 

 Golgi, an Italian, who studied the life-history of the 

 parasite in the blood and distinguished the three 

 forms which cause the three most familiar kinds 

 of malarial fevers, the tertian, the quartan and the 

 remittent types. From this time on this parasite 

 has been studied by physicians of many nationali- 

 ties and the whole course of its life-history worked 

 out. In order that we may understand how it was 

 that mosquitoes were determined to be the means 

 of disseminating this parasite we will discuss first 

 its life-history in the human blood. 



The parasites that cause the malarial fevers are 

 Sporozoans and belong to the genus Plasmodium. 

 Other names such as H&mamceba and Laverania 

 have been used for them, but the term Plasmodium 

 is the one now most commonly employed. The 

 three most common species are vivax, malarice 

 and falciparum, causing respectively the tertian, 

 quartan and remittent fevers. 



LIFE-HISTORY OF PARASITE 



The life-history of all of these is very similar, the 

 principal difference being in the length of time it 



