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Synopsis The Amphibians have sprung up from fish-like ancestors and that in turn given rise to reptiles. Thus, Amphibian consequently hold a very important intermediate position. The term Amphibia was coined by Linnaeus although he kept both, the Amphibians as well as some reptiles in this particular class. Later on naturalists and taxonomists put the Amphibians particularly in this class, although the characteristic features of the old Amphibians and those of recent are little more different. The main characteristics of Amphibians are: they may be, aquatic, terrestrial or both; these are cold-blooded (poikilothermous) animals. Their body temperature is variable and most of them undergo hibernation during winter. Some undergo aestivation during summer; the shape of body is variable, it may be depressed or cylindrical and divisible into head, neck, trunk and tail or into head and trunk. The skin is thin, moist, glandular and devoid of exoskeleton. There is a pair of nostrils, which open into the buccal cavity. They are provided with valves to exclude water. The teeth are alike (homodont) , acrodont and polyphyodont ; Endoskeleton is largely bony or ossified . Skill is dicondylic i.e. possesses two occipital condyles for the attachment to the vertebral column. Eyes are provided with movable lids and tear glands to clean and protect them in air. Brain has smooth cerebral hemispheres and the cerebellum is poorly developed. Fertilization is generally external, sometimes internal. Eggs are mesolecithal and are covered with gelatinous covering. They are laid in water. This encyclopaedic work in three volumes is designed to present entire vital information on Amphibia. Profusely illustrated in the light of latest researches, this work is a dependable reference work for students, teachers and researchers in the discipline.