70 



5. That the only practical steps found effectual were by clearing the 

 district of all shrubs, grass, bamboos, etc., in order to drive away the 

 adult female mosquitoes and then draining their breeding pools ; this 

 combination is absolutely essential, to treat the pools with any larvicide 

 alone means that they scatter and select other pools to lay their larvae 

 and breed from. 



In conclusion, these results corroborate recent investigation made 

 by others, and I believe if properly carried out, even over a limited 

 area, would free that district from the haunts of Anopheles^ and con- 

 sequently the horrors of malarial fever. It is no Utopian idea to think 

 that within a few years an island like Hong Kong or Stretton Island, 

 New York, may be cleared by our breaking the extra-corporeal life 

 circle of the malaria parasite. Within the last year I have visited 

 Sierra Leone and seen Major Ross at work, have seen the experi- 

 ments at Stretton Island, New York, under Dr. HOWARD, U.S. 

 Entomologist, and I unhesitatingly state that in none of these places 

 would I be more hopeful of the prevention of malaria than in Hong 

 Kong. 



Notes on Anti-Malarial Measures now being taken 

 in Lagos, by His Excellency Sir WILLIAM 

 MACGREGOR, K.C.M.G., C.B., M.D., Governor 

 of Lagos.* 



These few field notes to be read at a discussion on Malaria have 

 been written on the suggestion of Major RONALD Ross. The writer 

 of them is deeply sensible of the honour conferred on him by being 

 asked to prepare them a request which has very willingly been com- 

 plied with. 



The general outline of the natural history of the malarial parasites 

 is here accepted as sufficiently established for practical purposes by 

 the unique and glorious labours of Major Ross. In these notes, 

 therefore, only the practical aspects of the question are touched upon. 



* British Medicaljournal t 1901, vol. II., page 680. 



