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THE NATURAL HISTORY OF BOMBAY MALARIA 



BY 



Charles A. Bentley, M.B., CM. (Edin.), 



D.H.P., D.T.M.&H. (Camb.). 

 (With Plates I and II.) 



Natural History can show no more fascinating story than that 

 of the discoveiy of the Malaria Parasite, and the part played by 

 the mosquito in its transmission from man to man. Laveran and 

 Ross to whom we are indebted for this knowledge were medical 

 men, but they were naturalists too ; and the discoveries they made 

 would have been impossible but for this fact. Not so very long ago 

 a student of Natural History was looked upon as a crank who 

 delighted in collecting all sorts of specimens and pursued a study 

 which ordinary people considered largely a waste of time ; now-a- 

 days it is recognised that the whole science of Preventive Medicine, 

 especially as it relates to the problems of Tropical Disease, is based 

 upon the work of the one-time despised Naturalist. This being so, 

 I need offer no apology for addressing this Society upon such a 

 subject as The Natural History of Bombay Malaria, for Malaria is 

 as much a matter of interest to the student of Natural History as 

 to the medical man. 



In 1880 Laveran found when examining the blood of persons 

 suffering from malarial fever that small motile bodies could be seen 

 in the red blood corpuscles of the patients. Some of the bodies 

 were exceedingly minute and quite colourless but others were 

 nearly as large as the blood corpuscles themselves and contained 

 grains of blackish pigment in rapid motion. By a careful study 

 of these bodies at all stages in an attack of fever Laveran was able 

 to show that the occurrence of febrile paroxysms bore a direct 

 relation to the development of the organism which he was observ- 

 ing. Thus just before the onset of an attack of ague, numer- 

 ous large pigmented parasites were to be seen, but at the 

 moment when the first symptoms of shivering occurred, examina- 

 tion of the blood showed that these large pigmented parasites weve 

 dividing up into minuter forms and their pigment was being set 

 free in the blood. A little later in the attack the larger parasites 



