Plagiuri is an early (now disused) biological subclassification of fish (for example in Peter Artedi's Ichthyologia, and in early editions of Linnaeus's Systema Naturae). The term was invented by Artedi,[1][2] and is derived from the Greek πλαγιος (plagios; transverse) and ουρα (oura; tail).[3] The Pisces Plagiuri included those animals then classed as fish whose tails' flat surfaces faced anatomically up and down and not sideways.[3] Its members have now been shown to be mammals (including the whales and manatees).[2]

References edit