Source : Webster's Revised Unabridged Dictionary (1913)

Ganoidei \Ga*noi"de*i\, n. pl. [NL. See {Ganoid}.] (Zo["o]l.)
   One of the subclasses of fishes. They have an arterial cone
   and bulb, spiral intestinal valve, and the optic nerves
   united by a chiasma. Many of the species are covered with
   bony plates, or with ganoid scales; others have cycloid
   scales.

   Note: They were numerous, and some of them of large size, in
         early geological periods; but they are represented by
         comparatively few living species, most of which inhabit
         fresh waters, as the bowfin, gar pike, bichir,
         Ceratodus, paddle fish, and sturgeon.

Source : WordNet®

Ganoidei
     n : a group of mostly extinct primitive bony fishes
         characterized by armor-like bony scales [syn: {order
         Ganoidei}]