Any of several varieties of reptiles that can live in fresh water, salt water or on land and have a hard shell covering their bodies. Some turtles can grow quite large, weighing over 1,000 pounds. For cooking purposes the sea or green turtle -- found in temperate marine waters is best known. It has a smooth olive green shell and green to whitish flesh; the green flesh is considered superior. These turtles are often made into a thick turtle soup that usually includes Maderia or Sherry as an ingredient. Terrapin, a small (7- to 8-inch) turtle species that inhabits fresh or brackish water, is considered by many to have the best meat. Terrapin meat is sometimes pounded and served like steak. Tortoises live on land and are considered less desirable than terrapin or sea turtles. Regardless of the species, the meat of the female is much more tender than that of the mate. Conservation measures have limited the availability of this reptile, but some turtle meat can be found in East Coast markets, along the Gulf Coast and in Chinese markets in various regions. Canned and frozen turtle meat can sometimes be found in specialty food stores.