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but no flagellulae were observed in their salivary glands ; 

 also several observers allowed themselves to be freely bitten 

 by newly bred mosquitoes taken from malarial districts, but 

 in no case were any ill effects experienced. All the evidence 

 so far tends to show that those Anopheles which have 

 not bitten malarial patients are not infected, and are not 

 capable of inoculating the disease. 



Professor Koch last year was the head of a German com- 

 mission appointed for the study of malaria in Italy. He 

 found the characteristic parasites in the blood in all the 

 eases examined. 



Apart from the blood of human beings the parasite was 

 only found in some species of mosquitoes which were only 

 met with in the summer. He also proved that the mos- 

 quito conveyed the parasite from one person to another. 



It was found that the parasite required a temperature 

 of 8o° F. to develope in the mosquito, therefore it was 

 only found in these insects in the summer months. He 

 found also that Culex pipicns was concerned in propagating 

 the disease in Tuscany, but only to a very small extent. 

 He found that the infection was maintained and propa- 

 gated during the nine months of the year when the tem- 

 perature is below 8o° F. by the relapsing cases which 

 continue all the year round, and form the link between 

 one fever season and the next ; so that in the beginning 

 of summer mosquitoes can always find parasites, which 

 undergo the series of changes described above in their 

 bodies, and then, later, may be injected into some new 

 host, and so the fever is spread. 



If no relapse occurred in any of the cases of malaria in 

 any given district, the mosquito would find no parasites 

 in the beginning of summer, and consequently, malaria 

 would become extinct there. 



Koch found certain species of mosquito in the houses, 

 and noted that they only bit at night, therefore the in- 

 habitants became infected at night in their own houses. 



Drs. Monaco and Panichi have studied the effects of 

 solutions of quinine of varying strength in causing the 

 exit of the parasites from the red blood-corpuscles, when 

 they are in the adult stage. Very dilute solutions only 

 excited them, while in less dilute solutions they were com- 

 pelled to go out of the corpuscles ; while strong solutions 

 paralysed them. If now it is found possible that relapses 

 may be entirely prevented by the proper use of quinine, 

 malaria would be stamped out in those countries where 



