Lattice Leaf

Lattice Leaf, also called LACE LEAF, WATER-YAM, or OUVIRANDRANO (Ouvirandra fenestralis), an aquatic plant belonging to the natural order Juncagineæ. It is best known as the lattice-leaf plant, from the singular resemblance of the leaves to open lattice-work. The plant is a native of Madagascar, and was introduced into England about 1850 by the Rev. W. Ellis. It grows on the margins of running streams in shallow water. The leaves grow in radiating clusters, and float immediately under the surface of the water; in outline they are oblong, rounded at base and point, from 9 to 12 inches long. Their peculiar structure is due to the absence of the cellular tissue which fills up the spaces between the nerves or veins of ordinary leaves, the veins, which in this instance are almost geometrically parallel longitudinally and transversely, being alone coated with cellular matter and parenchyma. The flower-stems rise to the surface of the water and there divide into two spikes of flowers, which are accompanied by conspicuous white bracts. The plant is not only curious but useful as an article of food to the natives, who eat the yam-like roots. The native name of the plant is Ouvirandrano, which means literally water-yam. There are several other species of Ouvirandra, but none so remarkable and interesting as the lattice-leaf plant, which is frequently to be seen growing in hothouses. See AQUATIC PLANTS for illustration.