The Hormones: Physiology, Chemistry, and Applications, Volume IV provides information pertinent to the nature and function of hormones. This book presents unexpected findings in such diverse fields as the nature and activities of glucagon, the hormones regulating insect growth, as well as the synthesis, metabolism, and secretion of the catecholamines. Organized into 11 chapters, this volume begins with an overview of the diversity of physiological effects of auxins. This text then explores the chemical nature, mechanisms of inactivation, and mode of synthesis of insect growth hormones. Other chapters consider hormone participation in some processes among coelenterates, platyhelminths, and echinoderms. This book discusses as well the status of information on endocrine mechanisms in the lower vertebrates. The final chapter deals with the potential advantages of immunoassay over bioassay procedures, which include high sensitivity and specificity. This book is a valuable resource for organic chemists, biochemists, endocrinologists, morphologists, physiologists, students, and research workers.