272 HYDROCIIARIDE^E. {Ihjdrocharis. 



ous. — Fertile Jl. Calyx 3-leaved. Petals three. Pistils very 

 numerous, collected into a head. Pericarps 1-seeded, com- 

 pressed, margined. — Named from sagitta, an arrow, from the 

 shape of the leaves. Moncecia. Polyandria. 



1. S. sagiftifolia, Linn. Common Arrow-head. Leaves ar- 

 row-shaped, the lobes lanceolate, straight. Br. Fl. 1. p. 406. 

 E. Fl. v. iv. p. 144. E. Bot. t. 84. 



Ditches and margins of rivers. Plentiful in the County of Ferma- 

 nagh, where it had been previously noticed by Dr. Scott, and banks of 

 the Shannon, near Portumna. In the Lagan river near Lough Neagh ; 

 Mr. Templeton. In the lake at Killikeen, and at Drigget, County of 

 Cavan ; liev. Mr. Halpin. Fl. July, Aug. %. — A beautiful aquatic, 

 with large, truly arrow-shaped leaves, rising above the water. 



Ord. 79. HYDROCHARIDE^. Juss. Frog-bit Family. 



Flowers perfect or separated. Perianth semipetaloid, 3 — 6- 

 cleft, in the fertile flowers adherent with the ovary. Stamens 

 definite or indefinite. Ovary one: stigmas many. Pericarp 

 baccate or capsular, without valves, 1- or many-celled. Seeds 

 without albumen. Plumule inconspicuous. — Aquatic, herba- 

 ceous plants. Leaves with parallel veins. Flowers spathaccoas. 



1. Stratiotes. Linn. Water-Soldier. 



Spaiha of two leaves. Calyx 3-cleft. Corolla of three petals. 

 Berry inferior, angular, with six cells, many-seeded. — Name 

 from arpaToi, an army, on account of the numerous sword- 

 like leaves. Polyandria. Pentagynia. 



1. S. aloides, Linn. Water- Soldier. Leaves sword-shaped, 

 triangular, with a prominent rib and sharp marginal prickles. 

 Br. Fl. 1. p. 262. E. Fl. v. iii. p. 34. E. Bot. t. 379. 



Lakes and ditches or drains ; near Crum-castle and Castle-Saun- 

 derson an the banks of Lough Erne ; also on the banks of the Shan- 

 non, near Portumna. Belfast water-course ; Mr. Templeton. Fl. 

 July. %. — A singular plant, resembling an Aloe, with numerous radi- 

 cal leaves thrown up from creeping runners, which penetrate far and 

 deep in the mud. Scape four to six inches long, compressed, two- 

 edged. Flowers white from the compressed two-leaved sjiatha. 

 Sometimes the jloivers are dioecious, and sometimes the stamens are 

 on the flower with the 5 or G-cleft styles. 



2. Hydrocharis. Linn. Frog-bit. 



Flotvcrs spathaceous. Barren jl. Calyx in three deep seg- 

 ments. Corolla of three petals. Stamens nine, in three 

 rows, within which are three imperfect styles. Fertile Jl. 

 Calyx in three deep segments. Petals three. Styles six, 



