HYDROCHARIDACE^— FROG-BIT TRIBE 205 



Class II. MONOCOTYLEDONOUS PLANTS. 



The plants of this class have only a single cotyledon or seed-lobe to 

 their embryo; first-formed leaves alternate with each other. The stem is 

 composed of woody fibre, cellular tissue, and spiral vessels ; but there is no 

 true bark or pith, nor is there any trace of concentric annual layers, but 

 wood and cellular tissue are mixed together. The stem increases by the 

 addition of new matter within : hence the term Endogenous, or Inward 

 Growers, is often applied to these plants. In our country the Monocoty- 

 ledons are all herbaceous, and they may, in general, be readily distinguished 

 by their leaves. These are commonly alternate, sheathing, and, in almost 

 all cases, their veins run in parallel lines from the base to the point of the 

 leaf, the principal veins being connected by nearly simple secondary veins, 

 as in the Orchises and Grasses ; while, in the Dicotyledons, the veins diverge 

 from the midrib to the margins of the leaves, and are connected by smaller 

 veins branching in all directions, and forming a network, as in the leaves of 

 the rose or bramble. The flowers of Monocotyledons have stamens and 

 pistils— three, or some multiple of three, being the number which pre- 

 dominates in the parts of fructification — and they are with or without a 

 perianth. A large number of plants, forming Sub-class II., Glumacese, have 

 chaffy scales or glumes, instead of sepals and petals. This Sub-class comprises 

 the true Grasses, and their allies, the Sedges and Sedge-like plants. 



Sub-class I. Petaloide^e. 



Flowers having petals arranged in a circular manner ; or without petals. 



Order LXXXII. HYDROCHARIDACEiE— FROG-BIT 



TRIBE. 



Flower-buds enclosed in a sheath ; sepals 3, green ; petals 3 ; stamens 3, 

 9, 1 2, or more ; ovary inferior, 1 or many-celled ; styles 3 or 6 ; stigmas 

 3 — 6 ; fruit dry or juicy, not bursting, 1 or many-celled. The plants of this 

 order are floating aquatics, possessing no important properties. 



1. Anacharis. — Stamens and pistils on different plants ; barren flower, 

 having a 6-parted perianth and 9 stamens ; fertile flower with a long thread- 

 like tubular spathe, 3 sterile stamens, and 3 stigmas ; capsule 1 -celled, few- 

 seeded. Name said by the authors of the "British Flora" to be from the 

 Greek ana, like, and charis, an abbreviation of the next genus. 



2. Frog-bit (Hydnkharis). — Stamens and pistils on different plants; 

 stamens 12, 3 or 6 wanting anthers; ovary 6-celled; stigmas 6. Name from 

 the Greek liydor, water, and charis, elegance. 



3. Water Soldier {Stmtiutes). — Stamens and pistils usually on different 

 plants ; stamens 1 2, surrounded by many imperfect ones ; ovary 6-celled ; 

 stigmas 6. Name from the Greek word for a soldier, because of its prickly, 

 sword-shaped leaves. 



1. Water-thyme {Anacharis). 



Water-thyme {A. alsindstrum).- — Leaves 3 or 4 in a whorl, linear, or 

 oval oblong, thin, and minutely serrated ; perennial. This plant, which is 



