"Ichthyology Handbook" provides comprehensive information on how an ectothermic chordate occupying the base of evolutionary scale, successfully confronts the diverse, everfluxing and stressful milieu. This book introduces the reader to the insights of diverse facets of fish life with emphasis on evolution and phylogeny; skin as an outfit of offence and defence; feeding repertoires; predator-prey relationship; motion, equilibrium and stability; secondary vascular system; respiratory tissues and designs; elimination of nitrogenous waste-products; modes of reproduction, and their functions; sophistication of sensors of natural stimuli; electrogenic and photogenic tissues; migratory behaviour and imprinting; life in unique niches; diseases and control systems and regeneration. The entire text of organ-systems is a testimony to the mastery of this fascinating organism for survival in an aquatic environment.