- n Agnatha superclass of eel-shaped chordates lacking jaws and pelvic fins: lampreys; hagfishes; some extinct forms
Century Dictionary and Cyclopedia
- Agnatha A section of geophilous gastropods destitute of jaws.
- Agnatha A class of fishes, or fishlike vertebrates, characterized by the absence of jaws and shoulder-girdle. It contains the extinct ostracoderms and the existing lampreys.