Synopsis The present publication provides information on various essential aspects of entomology in eleven chapters. It covers Intake system, Exchange of gases, Internal transportation, Outgo apparatus, Dominating entry, Ports of entry, Preservation of species, Embryonic development, Hatching, Developmental anomaly and Transformation etc. An effort has also been made to illustrate each aspect with comprehensive text, suitable diagrams and up-to-date generic names. It is hoped that the present book will cater the need of undergraduate and postgraduate students studying entomology in several universities.