calla or calla lily: see arum.

Either of two distinct kinds of plants of the arum family. Calla palustris is known as the arum lily, water arum, or wild calla. The common name calla is also generally given to several species of Zantedeschia, often called calla lilies. The handsome C. palustris occurs widely in wet places in cool, northern temperate and subarctic regions. It has heart-shaped leaves, showy white floral leaves, and clusters of brilliant red berries. Its juice is violently poisonous. The most important of the calla lilies, all native to South Africa, is the common florist's calla (Z. aethiopica), a stout herb with a fragrant white spathe and arrow-shaped leaves; a popular indoor plant, it is grown commercially for cut flowers.

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