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Webster 1913 Edition
Rhizostomata
‖
Rhiˊzo-stom′a-ta
,Noun.
pl.
[NL., fr. Gr. [GREEK][GREEK][GREEK] a root + [GREEK][GREEK][GREEK], [GREEK][GREEK][GREEK][GREEK], a mouth.]
(Zool.)
A suborder of Medusae which includes very large species without marginal tentacles, but having large mouth lobes closely united at the edges. See Illust. in Appendix.