METEOROLOGY AND CLIMATE. 203 



and retaining most of this heat, the radiation of a 

 single clear night would chill down the land far 

 more than the solar energy received during the 

 day could heat it." 



The life history of malaria germs is not by any 

 means completely known. A very excellent ac- 

 count b}^ Dr. P. Manson will be found in the 

 British Medical Journal, April 15, 1893. There is 

 also a good summary in Natural Science, vol. v., 

 No. 31, September, 1894, by Dr. Gregory. From 

 these the life history of the germs within the body 

 can be easily understood. I do not think, however, 

 that our knowledge of the manner in which they 

 are introduced into the blood is at all satisfac- 

 tory. Dr. Manson has a most attractive theory 

 that the mosquito receives malarial germs — a most 

 gratifying idea to every one who has suffered from 

 mosquitoes, as I have done ! 



As far as I can understand, for the question is 

 certainly one which is not by any means fully 

 explained, the mosquito, like man, suffers from 

 fever, and is able to extract the malarial germs 

 with human blood ; this is, of course, obviously 

 possible. The disease may then be passed from 

 mosquito to mosquito, and thus kept alive. It 

 may become encysted on the death of the mosquito, 

 and may be in this condition swallowed or breathed 

 by travellers. 



Personally, I supposed that the marriage flight 

 of mosquitoes occurs just before sunset, and that 



