CHAPTER I 



THE IMPORTANCE OF DOMESTIC MOSQUTTOS 



As described in the Introduction, it was the dis- 

 covery that malaria is conveyed by mosqui tos which 

 first seriously directed attention to the different 

 varieties of that insect. For years, in India, Ross 

 had attempted to transmit intermittent fever by 

 the common grey gnat and by the speckled gnat ; 

 but the attempts were unsuccessful. Then came 

 the discovery that malaria is conveyed from one 

 human being to another by the dapple-wing mos- 

 quito, or Anopheline. This led to the classification of 

 these insects. Mr. Theobald's classification is decided 

 largely by the shape and form of the microscopic 

 scales which cover the bodies and the veins of the 

 wings of gnats, and also by the anatomy of their 

 proboscides, etc. In this way mosquitos have been 

 separated into a number of subfamilies, genera, 

 and species. This is the scientific classification. 



But there is another classification that is simpler 

 than this : it is based on the habits of the different 

 species. The type of mosquito that inhabits houses 

 in towns or compactly built villages is different from 

 the type that lives in marshes, forests, and on the 



16 



