Amphibia (the amphibians) is a class of vertebrate animals, which in their early life breathe by gills or branchiae, and afterwards partly or entirely by lungs. The Frog, breathing in its tadpole state by gills and afterwards throwing off these organs and breathing entirely by lungs in its adult state, is an example of the latter phase of amphibian existence. The Proteus of the underground caves of Central Europe exemplifies forms in which the gills of early life are retained throughout life, and in which lungs are developed in addition to the gills. A second character of this group consists in the presence of two occipital condyles, or processes by means of which the skull articulates with the spine or vertebral column; Reptiles possessing one condyle only. The class is divided into four orders: the Ophiomorpha (or serpentiform), represented by the Blind-worms, in which limbs are wanting and the body is snake-like ; the Urodela or Tailed Amphibians, including the Newts, Proteus, Siren, etc; theAnoura, or Tailless Amphibia, represented by the Frogs and Toads; and the Labyrinthodontia, which includes the extinct forms known as Labyrinthodons. Research Amphibia
Abbreviations
Nature
Research Amphibia