This book describes cellular, biochemical, immunological and hormonal studies during development of the female reproductive system of the red cotton stainer, Dysdercus koenigii (Heteroptera: Pyrrhocorridae) with special emphasis on the synthesis, sequestration and hormonal regulation of the egg proteins, vitellin and vitellogenin. The major egg protein, vitellin, has been characterised and its synthesis in fat bodies and its sequestration into ovaries has been described using cellular, biochemical and immunological methods. Effects of juvenile hormone on vitellogenesis of this bug has also been studied, and the effect of Azadirachtin, an insect growth regulator from the neem plant, Azadirachta indica, has been investigated by hormonal application and surgical interventions on the corpora allata of the bug. Works detailed in this book, in full, formed the doctoral thesis of the author, Venugopal K.J. in the Banaras Hindu University, India, and have been published as peer-reviewed research papers in science journals, and presented in science conferences.