They are often seen riding the waves of the ocean. They can also be found in rocky pools and in marshlands. They are clothed in a shimmery substance looking like water but shinning with all the colors of the sea, with green predominating. The concept of the mermaid is connected with these elemental beings. The undines also work with the plants that grow under the water and with the motion of water.
Some undines inhabit waterfalls, others live in rivers and lakes.
Every fountain has its nymph. Every ocean has its oceanids. The undines closely resemble humans in appearance and size, except for those inhabiting smaller streams and ponds. The undines often live in coral caves under the ocean or on the shores of lakes or banks of rivers. Smaller undines live under lily pads.