• Webster's Revised Unabridged Dictionary
    • n. pl Nematognathi (Zoöl) An order of fishes having barbels on the jaws. It includes the catfishes, or siluroids. See Siluroid.
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Century Dictionary and Cyclopedia
    • nematognathi An order of teleost fishes in which the supramaxillary bones are lateral and short or rudimentary, and covered with skin which forms barbels at each corner of the mouth, whence the name; the nematognaths or catfishes. The intermaxillaries are closely apposed to the ethmoid and immovably fixed; there is no subopercular; the four anterior vertebræ are coalesced into a single piece; and elements are detached to form bones which connect the air-bladder with the organ of hearing. Nematognaths have no true scales; they are either naked or have appendages developed as plates on all or a part of the body. About 800 species are known; they are specially numerous in tropical waters, both fresh and salt. By some authors all have heen referred to one family, Siluridæ; by others from 3 to 12 families are admitted. They are most closely related to plectospondylous fishes, as the characinids and cyprinoids. The two most prominent families are Siluridæ proper and Loricariidæ. See cuts under Siluridæ and Loricaria.
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Webster's Revised Unabridged Dictionary
NL. See nemato-, and Gnathic