What is "naked-eyed medusae"

Hydromedusa \Hy`dro*me*du"sa\, n.; pl. Hydromedus[ae]. [NL. See Hydra, and Medusa.] (Zo["o]l.) Any medusa or jellyfish which is produced by budding from a hydroid. They are called also Craspedota, and naked-eyed medus[ae].

Note: Such medus[ae] are the reproductive zooids or gonophores, either male or female, of the hydroid from which they arise, whether they become free or remain attached to the hydroid colony. They in turn produce the eggs from which the hydroids are developed. The name is also applied to other similar medus[ae] which are not known to bud from a hydroid colony, and even to some which are known to develop directly from the eggs, but which in structure agree essentially with those produced from hydroids. See Hydroidea, and Gymnoblastea.

Medusa \Me*du"sa\, n. [L., fr. Gr. ?.]

1. (Class. Myth.) The Gorgon; or one of the Gorgons whose hair was changed into serpents, after which all who looked upon her were turned into stone.

2. [pl. Medusae.] (Zo["o]l.) Any free swimming acaleph; a jellyfish. Note: The larger medus[ae] belong to the Discophora, and are sometimes called covered-eyed medus[ae]; others, known as naked-eyed medus[ae], belong to the Hydroidea, and are usually developed by budding from hydroids. See Discophora, Hydroidea, and Hydromedusa. Medusa bud (Zo["o]l.), one of the buds of a hydroid, destined to develop into a gonophore or medusa. See Athecata, and Gonotheca. Medusa's head.

   1. (Zo["o]l.) An astrophyton.

   2. (Astron.) A cluster of stars in the constellation Perseus. It contains the bright star Algol.