The finned porpoises, species of the genus Phocoena, have a dorsal fin. They are distributed throughout the world and include the harbour, or common, porpoise, P. phocoena, found throughout the Northern Hemisphere. The vaquita, P. sinus, found only in the N Gulf of California, Mexico, is the smallest and most endangered species. The finless porpoises, genus Neophocaena, are found in the Indian and W Pacific oceans and in the Chang (Yangtze) River.
The fat of the porpoise yields a lubricating oil, and the flesh is sometimes eaten. In North America the dolphins (family Delphinidae) are sometimes called porpoises and the bottle-nosed dolphin is sometimes called the common porpoise. True porpoises are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Cetacea, family Phocoenidae.
See W. N. Kellogg, Porpoises and Sonar (1961); K. S. Norris, ed., Whales, Dolphins and Porpoises (1966) and, as author, The Porpoise Watcher (1974); R. Ellis, Dolphins and Porpoises (1989).
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
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