• Webster's Revised Unabridged Dictionary
    • n. pl Physostomi (Zoöl) An order of fishes in which the air bladder is provided with a duct, and the ventral fins, when present, are abdominal. It includes the salmons, herrings, carps, catfishes, and others.
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Century Dictionary and Cyclopedia
    • n physostomi An order of teleost fishes established by J. Müller in 1845, containing those whose air-bladder, when present, is connected with the alimentary canal by an air-duct, the bladder thus having an outlet or mouth: contrasted with Physoclisti. The order was divided by Müller into 2 suborders and 14 families. It includes most of the abdominal malacopterygian fishes of the older authors. In Cope's system of classification it is ranked as a primary group of actinopterous fishes, with the basilar segments of the ventral fin rudimental and abdominal, the parietal bones usually united. branchiostegal rays developed, and the pneumatic duct open. It includes, in addition to the forms recognized by Müller, certain ganoids, as the Amiidæ(order Halecomorphi) and Lepidosteidæ (order Ginglymodi). See cuts under Percopsis, pike, and Esox.
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Webster's Revised Unabridged Dictionary
NL., fr. Gr. a bellows + mouth


In literature:

Bony fishes with air passage to the swimming bladder (Physostomi); 25.
"The History of Creation, Vol. II (of 2)" by Ernst Haeckel