46 DISCOVERY OF THE PARASITE OF MALARIA 



now used, and the secret was revealed. The contents 

 of the mature pioinented cells did not consist of clear 

 fluid, but of a multitude of delicate, thread-like bodies, 

 which, on the rupture of the parent cell, were poured 

 into the body cavity of the insect. They were evi- 

 dently spores." 



Further on in his narrative he shows how the spores 

 here described enter the salivary gland of the mosquito. 



" The exact route of infection of this great disease, 

 which annually slays its millions of human beings, and 

 keeps whole continents in darkness, was revealed.^ 

 These minute spores enter the salivary gland of the 

 mosquitos, and pass with its poisonous saliva directly 

 into the blood of man. K^ever in our dreams had we 

 imagined so wonderful a tale as this." 



Finally Ross, in order to make a crucial test of the 

 accuracy of his obser\ations, in 1898 infected twenty- 

 two out of twenty-eight healthy sparrows by mosquitos 

 previously fed on diseased sparrows. 



In 1900 INIanson infected two gentlemen in London 

 by mosquitos brought from Italy. They were infected 

 in Italy by allowing them to suck up a meal of blood 

 from a man suffering from malaria. One of the gentle- 

 men who submitted himself to be bitten in England by 

 these infected mosquitos was Manson's own son. As the 

 result of the bite the latter contracted tertian malaria 

 and tlie parasites were found in his blood. The first 

 attack was followed by recurrences. This experiment 

 demonstrated that a person could contract malaria in 



' Rouald Ross, " Researches ou Malaria^" Loudon, lUOo, pp. 32, 33, 

 and 34. 



