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results of our search, we direct attention to two important points: (i) 

 that the breeding pools that proved most important, and which even 

 at this late date in the year contain abundant larvae, are within 80 

 yards of the police station, and 40 yards from the matshed occupied 

 by the civil staff ; and (2) that the marshy stream above referred to is 

 a permanent and prolific breeding ground. 



We examined under the microscope the blood of ten children from 

 the village nearest fro the police station. 



****** 



In 50 per cent, of the cases examined we found the parasites 

 of malaria ; 2 cases were of benign type and 3 malignant, and while 

 all five children were infective to the mosquito, rendering any Ano- 

 pheles feeding upon them capable of a few days later transmitting the 

 disease to other persons, in 2 cases the form of the parasite that 

 actually came under our observation was the gamete, namely, the 

 form which when ingested by the mosquito is capable of undergoing 

 metamorphosis in the body of that insect. 



In the abundance of mosquitoes of the Anopheles genus above 

 described, with their breeding-grounds almost close up to the Govern- 

 ment buildings, and in the near proximity of an extensively infected 

 native population, by which many of these mosquitoes are being con- 

 tinuously rendered infective to healthy persons who may be bitten by 

 them, we have the factors that account sufficiently and conclusively 

 for the fevers that have prevailed among the Government officers at 

 Tai-po. 



We are of opinion that the seasonal increase of fever cases that 

 has been observed at the time of ploughing, and at the period of 

 harvesting the two rice crops, is due to the disturbance at these times 

 of mosquitoes usually resting among the grass or growing paddy, and 

 feeding on Chinese coming within their reach, such disturbance 

 resulting in their flying further afield and finding their way in large 

 numbers to the houses on the hills. 



I would emphasise the practical impossibility of dealing with the 

 larvae of mosquitoes by any germicide on account of the hidden nature 

 of many of their breeding places, which were only found after the 

 undergrowth was removed ; and on account of the luxurious vegeta- 

 tion in which the adult mosquitoes live. Culicicides, petroleum gas, 

 lime, gallol, etc., are only subsidiary measures, although undoubtedly 

 useful. 



The only permanent and effectual method seems to be that adopted 



