Classification
As H.J. Rose states, all the names for various classes of nymphs are plural feminine adjectives agreeing with the substantive nymphai, and there was no single classification that could be seen as canonical and exhaustive. Thus the classes of nymphs tend to overlap, which complicates the task of precise classification. Rose mentions dryads and hamadryads as nymphs of trees generally, meliai as nymphs of ash trees, and naiads as nymphs of water, but no others specifically.
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