Parameter Tree:
EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > ANIMALS/VERTEBRATES > AMPHIBIANS

Definition:
Amphibians are craniates with a permeable skin across which respiration
can take place. Their life cycle includes a shell-less egg which gives
rise to a distinct larval form. The amphibians are free living in fresh
water and on land (some are arboreal) but all are dependent on water or
damp conditions.


Reference:
Burn, David M. Animal World. 1980. Octopus Books Ltd. London.