626 AKACE.E — NAIADACEiE OE POTAME^. 



flag, has an aromatic odour, combined with a bitterish acrid taste. 

 It has been used as a stimulant and tonic. In Typha latifolia, Great 

 Eeed Mace, the pollen is abundant and easily collected, and from its 

 inflammable nature has been used as a substitute for the Lycopodium 

 spores. The rhizomes of Typha Shuttletaorthii, called Gortong, is 

 used by the Murray natives near Swanhill, Australia, as food. The 

 young shoots of T. latifolia and angustifolia are eaten by the Cossacks 

 like asparagus. The large, fleshy, amylaceous rhizomes are eaten by 

 the Kalmucks. Examples of large Aracese are seen in Oodwiniagigas 

 from Nicaragua, the root-stock of which weighs 5-6 lbs., the leaf- 

 stalk being 10 feet high, and the spathe 2 feet long, on a stalk 3 feet 

 high ; also in Archemone Hooheri, Dracontium asperum from Brazil, and 

 Gorynophallus Afaelii from western tropical Africa. Lemnas, Duck- 

 weeds, are common in ditches in temperate regions. Their flowers 

 are very simple, one male, and the other female, without a perianth, 

 enclosed in a membranous bag ; their roots are simple, covered with a 

 sheath. Golocasia esculenia, and other species, have edible corms, 

 which are called Eddoes and Cocoes in the West Indies. Fistia 

 Stratiotes floats in lakes in tropical countries. 



Order 211. — NAiADACE^a! or Potamb^, the Naias or Pondweed 

 Family. (Mono-JSypog.) Flowers hermaphrodite or unisexual. Pe- 

 rianth of two or four herbaceous or scaly pieces, often deciduous, 

 sometimes 0. Stamens definite, hypogynous. Ovary free, of one or 

 more carpels ; ovule solitary ; style 1 or j stigma 

 entire, rarely 2-3 parted. Fruit dry, 1-celled, usually 

 indehisceiit. Seed solitary, erect, or pendulous, exal- 

 buminous ; embryo straight or curved (flgs. 582, 583, 

 p. 331), usually with a lateral slit for the plumule 

 (fig. 868) ; radicle large (figs. 595, p. 334 ; 868).— 

 Plants living in fresh and in salt water, having cellular leaves with 

 parallel veins and inconspicuous flowers. They are found in various 

 parts of the world. They have no properties of importance. Zostera 

 marina is used in the dried state for stuffing mattresses, and has been 

 recommended for hospitals. Ouvirandra (Hydrogeton) fenestralis has 

 peculiar skeleton-like leaves. It is the lace-plant or lattice-plant of 

 Madagascar. Its rhizome is used for food under the name of water- 

 yam (ouvi, yam, and rano, water). Aponogeton distachyum, a Cape 

 aquatic, has grown well for many years in the open pond of the Edin- 

 burgh Eoyal Botanic Garden. Caulinia fragilis is one of the plants in 

 which Protoplasmic Rotation has been observed. There are 20 

 known genera and upwards of 90 species. Examples — Naias, Zanni- 

 cheUia (fig. 601, p. 337), Potamogeton (fig. 145, p. 81), Ruppia, Zostera. 



Kg. 868. Emtryo of Zostera, in the natural order Naiadaoese. c, Cotyledon, r, Radicle. 

 6, Lateral swelling connected with the radicle. /, Slit for the plumule, which lies in a 

 cavity of the very large radicle. 



