Human and economic factors are involved in the diseases for which mosquitoes are held responsible,- yellow fever, encephalitis, malaria -- hence the need, it is to be assumed, for a book like this. Marston Bates writes from ""east of the Andes and west of nowhere"" -- and explores the mosquito -- its behavior, the biology thereof, the research devoted to the subject, and its results. Apparently an enormous literature already exists on the subject; this purports to sort and organize the facts, indicate the gaps in knowledge, the importance of combining field and laboratory observation. ""Natural History"" is here confined chiefly to ecology and physiology of mosquitoes:- environment, dispersal, sexual behaviour, classification, species, and so on. Not to be original, I can frankly say- this book tells more about mosquitoes than I care to know. However, it isn't written for the layman.