CALLA

a genus of Araceze with the single species, C. palustris, bog arum, found in marshes of N. Europe. The leaves. are cordate, not sagiltate, and the hermaphrodite flowers, ‘borne every two years, are enveloped in a beautiful white spathe. Richard i a aethiopica, the Egyptian lily, or lily of the Nile, was formerly included in this genus.