Hydra

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Hydra

a genus of the coelenterate class Hydrozoa. Most species are found in freshwater, and are unusual members of the Hydrozoa in not having an ALTERNATION OF GENERATIONS.
References in periodicals archive ?
For a change of pace, jump from Nu to Mu ([mu]) Hydrae, then look a half binocular field south for the 7.
4 cm lie within the disk that surrounds TW Hydrae, Wilner and his colleagues report in the June 20 Astrophhisical JournaI Letters.
East of Mu Hydrae is brighter Nu Hydrae--and they form the base of an equilateral triangle whose northerly apex is U Hydrae, one of the reddest of all stars in binoculars and small telescopes.
For instance, if a faint dot of light in the TW Hydrae association really is a planet, it should move in 1 year a distance roughly equal to one-thirty-thousandth the width of the full moon on the sky, says Schneider.
These stars are C Hydrae and its attendants, which no longer belong to the Unicorn (Monoceros), according to modern constellation boundaries.
To my eyes, V Hydrae is much redder than its brighter neighbor.