Reptiles: Plate XXVII.

Title

Reptiles: Plate XXVII.

Description

Several illustrations of two different frogs and toads.

ca. 1840

Artist

Birhard

Historical Description

The terms amphibians (Amphibia) or amphibians include all terrestrial vertebrates which, in contrast to amniotes, can only reproduce in water. In amphibians, individual development generally takes place via an egg laid in water, from which a gill-breathing larva living in the water hatches. This larva undergoes metamorphosis, at the end of which there is usually a lung-breathing adult individual that is capable of living outside of water. Due to their physiology, however, all amphibian species are at least bound to habitats with high humidity even in the adult stage. Many amphibians are nocturnal in order to protect themselves from predators and to minimize water loss through the skin. Amphibians are considered the most primitive group of terrestrial vertebrates, partly because they are dependent on water for reproduction, because some parts of their skeleton do not ossify and because of the relatively low efficiency of their lungs and cardiovascular system. This distinguishes them from the higher land vertebrates, including birds and mammals, which are collectively referred to as amniotes.