MONOCOTTLEDONES 213 



Distribution. — They are widely distributed, but are chiefly 

 found in extra-tropical regions. Illustrative Genera : — Naias, 

 Willd. ; Zannichellia, Michel; Zostera, Linn. 



Properties and Uses. — Their properties are of little impor- 

 tance. 



Order 34. JuNCAGiNACEai, the Arrow- grass Order. — Cha- 

 racter. — Herbs, growing in marshes. Leaves with parallel 

 veins. Flowers hermaphrodite, whitish or greenish. Perianth 

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

 three pieces. Stamens 6, perigynous, anthers usually extrorse. 

 Carpels 3 — 6, separate or more or less united ; ovules 1 — 2. 

 Fruit dry, ultimately separating into as many parts as there are 

 carpels. Seeds attached- to axile or basal placentas, exalbumi- 

 nous ; embryo straight, with a lateral cleft. This order is in- 

 cluded by Bentham and Hooher in Naiadaceee. 



Distribution and Numbers. — The plants of this order are 

 found more or less in nearly all parts of the world, but are most 

 abundant in temperate and cold regions. Illustrative Genera : 

 — Triglochin, Linn. ; Potamogeton, Linn. There are about 50 

 species. 



Properties and Uses. — Of little importance. 



Series 7. — GUimacece. 



Order 35. Eriocatilace.?e, the Eriooanlon or Pipewort Order. 

 Character. — Aquatic or marsh plants, ieaues clustered, linear, 

 usually grass-like. Flowers minute, unisexual, in dense heads, 

 each flower arising from the axil of a membranous bract. 

 Perianth membranous, tubular, 2 — 3-toothed or -lobed. Stamens 

 2 — 6 ; anthers 2-ceUed, introrse. Ovary superior, 2 — 3-oeUed. 

 Fruit dehiscent, 2 — 3-celled, 2 — B-seeded. Seeds pendulous, 

 albuminous, hairy or winged ; embryo lenticular, at the end 

 of the albumen remote from the hilum. 



Distribution, Numbers, and Properties. — Mostly natives of 

 tropical America and the North of Australia. One species is 

 found in Britain, Eriocaulon septangulare. With. The order 

 contains about 200 species. Their properties are unimportant. 



Order 36. Desvauxiaces;, the Bristlewort Order. — Charac- 

 ter. — Small sedge-like herbs, with setaceous sheathing leaves. 

 Flowers glumaceous, enclosed in a terminal spathe. Glumes 1 

 or 2. PalecE none, or 1 or 2 scales parallel with the glumes. 

 Stamens 1 or very rarely 2 ; anthers 1-ceUed. Carpels 1 — 18, 

 distinct or partially united, with 1 stigma and 1 pendulous ovule 



