Webster's 1913 Dictionary
HOLOTHURIOIDEA
Hol `o *thu `ri *oi "de *a, n. pl. Etym: [NL. See Holothure, and -oid.](Zoöl.)
Defn: One of the classes of echinoderms.
Note: They have a more or less elongated body, often flattened beneath, and a circle of tentacles, which are usually much branched, surrounding the mouth; the skin is more or less flexible, and usually contains calcareous plates of various characteristic forms, sometimes becoming large and scalelike. Most of the species have five bands (ambulacra ) of sucker-bearing feet along the sides; in others these are lacking. In one group (Pneumonophora ) two branching internal gills are developed; in another (Apneumona ) these are wanting. Called also Holothurida, Holothuridea, and Holothuroidea.
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