The non-biting chironomid midges (Family Chironomidae, Order Diptera) include numbers of species whose larvae develop in bodies of fresh water and which play an important role in the transmission of nutrients along the food chain. They consume organic matter and microorganisms from the bottoms of these bodies of water, and then are themselves eaten by fishes and arthropods. They do not usually cause damage or transmit diseases, and as a result have been neglected by entomological research. But their usefulness in indicating levels of pollution and water quality conditions makes them important objects of study. This volume is a comprehensive summary of available information and research on the chironomid midges of Japan and East Asia: their taxonomy, biology, distribution, ecology, and relation to human life. It includes nearly 100 plates with copious detailed illustrations of the major genera and of the hypopygeal structures on which species identification is based. The extensive Key provides a guide to identifying all of the known chironomid species from Japan on the basis of the male genitalia. The authors, noted entomologists and experts on the Chironomidae, have compiled more than a century of research on these important insects into a single-volume reference work that will be useful not only to entomologists but also to environmental and public-health scientists.