from
The Collaborative International Dictionary of English v.0.48
Ganoidei \Ga*noi"de*i\, n. pl. [NL. See {Ganoid}.] (Zool.)
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.
[1913 Webster]
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.
[1913 Webster]