Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

First published in 1914, this volume was written in response to rising concerns regarding the role of the house-fly in the dissemination of infectious diseases, and its relationship to unhygienic conditions. Given the role played by the house-fly in these circumstances, it was decided that a thorough study of its entomological and medical significance was required. The volume was not intended as a popular treatise on the subject, this role had already been fulfilled by the author's House-flies and How they Spread Disease. Instead, it was designed for professionals in entomology and public health, together with students developing a specific interest in these areas. Numerous detailed illustrations of house-fly anatomy are included. This book will be of value to anyone with an interest in entomological studies and the history of public health.