EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > ANIMALS/VERTEBRATES > MAMMALS
The class Mammals are warm-blooded craniates with glandular skin which
is typically hairy; Young are fed on milk secreted by mammary glands.
Mammals are mostly terrestrial in all habitats from forest to desert, but
some fly and some inhabit freshwater or the sea.
Burn, David M. Animal World. 1980. Octopus Books Ltd. London.