690 



SYSTEMATIC BOTANY. 



of our commercial Sago is obtained. A single tree will yield from 150 to 

 200 pounds of Sago. (See Sagus.) The juice of the fruit is very acrid. 

 The stiff strong horsehair-like fibre known under the name of Gommnti 

 or Ejow fibre is derived from the leaf-stalks of this palm. 



Sagus. — From the trunks of S. Jcevis, S. ge7nnna, and other species, the 

 principal part of our Sago is obtained; from the former as much as 

 800 lbs. may be procured from a single plant. Sago is imported into this 

 country from Singapore. The average importation for some years has 

 exceeded 4,000 tons. Ah the Sago consumed in this country is derived from 

 these palms and t^aguerus saccharifer. (See Saguerus.) 



Seaforthia elegans.— This palm produces the Moreton Bay canes of com- 

 merce. 



Natural Order 270. Juncaginace^. — The Arrow-grass Order. 

 — C h a r a c t e r.— Herbaceous marsh plants. Leaves with parallel 

 veins. Flozvers perfect, whitish or greenish. Perianth small, 

 more or less scaly, inferior, in two whorls, each containing three 

 pieces. Stamens 6 ; anthers usually extrorse. Carpels 3 — 6, 

 separate, or more or less united; ovules 1 — 2. Fruit dry, ulti- 

 mately separating into as many parts as there are carpels. 

 Seeds attached to axile or basal placentas, without albumen ; 

 embryo straight, with a lateral cleft {figs. I'^'l and 748). 



Distribution, ^x. — Found more or less in nearly all parts of 

 the world, but most abundant in temperate and cold regions. 

 Examijlcs of the Genera : — Triglochlin, Potamogeton, Ouvirandra. 

 There are about 50 species. 



Properties and Uses. — Of little importance. 



Ouvirandra fmestralis, a native of Madagascar, is known under the name 

 of the Lattice-leaf plant, from its leaves resembling open lattice-work. Its 

 roots are of a fleshy farinaceous nature, and form an article of food ; hence 

 the name Ouvirandram, by which the plant is known in Madagascar, the 

 literal meaning of which is Water -yam. 



Natural Order 271. Alismace,^. — The Alisma Order {figs. 

 1061 and 1062). — Character. — Swamp or floating plants. 



Fig. 1061. 



Fig. 1062. 



Fig 1061. Flower of a species of Alisma, with an inferior perianth, 

 arranged in two whorls, earh consisting of three parts ; six stamuns ; 

 and numerous carpels. Fig. 1062. Vertical section of the same flower. 



Leaves narrow or with an expanded lamina, parallel-veined. 

 Flowers perfect {figs. 1061 and 1062), or very rarely unisexual. 



