Nymphs

"Hylas and the Nymphs" by John William Waterhouse, 1896

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From Wikipedia:

A nymph in Greek mythology is a female spirit typically associated with a particular location or landform. Other nymphs, always in the shape of young nubile maidens, were part of the retinue of a god, such as Dionysus, Hermes, or Pan, or a goddess, generally Artemis.[1] Nymphs were the frequent target of satyrs. They live in mountains and groves, by springs and rivers, also in trees and in valleys and cool grottoes. They are frequently associated with the superior divinities: the huntress Artemis; the prophetic Apollo; the reveller and god of wine, Dionysus; and rustic gods such as Pan and Hermes.

The following is not the Greek classification, but is intended simply as a guide:

Land Nymphs
Alseids (glens, groves)
Auloniads (pastures)
Hesperides (nymphs of the west, daughters of Atlas)
Aegle ("dazzling light")
Arethusa
Erytheia (or Eratheis)
Hesperia (or Hispereia)
Leimakids (meadows)
Minthe (mint)
Napaeae (mountain valleys, glens)
Oreads (mountains, grottoes)
Pleiades (daughters of Atlas and Pleione; constellation)
Maia (partner of Zeus and mother of Hermes)

Wood nymphs
Dryads (trees)
Hamadryads (oak tree and others)
Epimeliad (apple tree)
Leuce (white poplar tree)
Meliae (manna-ash tree)

Water nymphs ("Ephydriads")
Helead (fen)
Naiads (usually fresh water)
Crinaeae (fountains)
Eleionomae (marshes)
Hyades (rain)
Limnades or Limnatides (lakes)
Pegaeae (springs)
Potameides (rivers)
Corycian Nymphs (Corycian Cave)
Nereids (daughters of Nereus, the Mediterranean Sea)
Oceanids (daughters of Oceanus and Tethys, any water, usually salty)
Sabrina (the river Severn)

Other Nymphs
Lampades (underworld)
The Muses
Nephelae (clouds)

What's your favorite Nymph??? - mine are the Limnatides

more info: http://en.wikipedia.org/wiki/Nymph