68 ENGLISH BOTANT. 



Sub-Order II,— ALISME^. 



Perianth with the 3 outer segments herbaceous, the 3 inner larger 

 and petaloid. Stamens 6 or more; anthers introrse, rarely extrorse. 

 Seeds 1 or 2 in each cell of the ovary ; embryo hooked. 



GENUS IIL—S AGITTARIA. Linii. 



Powers moncEcious. Perianth with the 3 outer leaves herbaceous, 

 Bubpersistent, the 3 inner leaves larger and petaloid, caducous. Male 

 flowers with numerous hypogynous stamens; filaments filiform; 

 anthers extrorse, affixed by the base. Female flowers with the ovaries 

 very numerous, free, 1-celled and 1-ovuled ; stigma simple. Fruit of 

 numerous capitate achenes. 



Marsh herbs with the rhizome throwing off runners terminating in 

 bulbs, which produce plants in the succeeding year. Leaves stalked, 

 triangular and then hastate or cordate or strapshaped, the earlier ones 

 without an)^ lamina and submerged or floatmg. Flowers white or lilac, 

 in a raceme on a scape with verticellate peduncles; the male flowers 

 at the top and the female below them. 



The name of tliis genus of plants conies from sagitta, an arrow, wticli the leaves of 

 the species are thought to resemble. 



SPECIES I.— S A GIT TAR I A S AGITTIPO LI A. Linn. 



Plate MCCCCXXXVI. 



Beich. Ic. Fl. Germ, et Helv. Vol. VII. Tab. LHI. Kg. 94. 

 Billot, Fl. GaU. et Germ. Exsicc. No. 2913. 



Submerffed leaves (phyllodia) linear-strapshaped or linear-oblance- 

 olate, submerged or floating at the apex, translucent ; aerial leaves 

 sagittate with straight acute basal lobes. Scape simple. Peduncles 

 whorled, those of the fertile flowers not half as long as those of the 

 sterile flowers. Filaments subulate, longer than the anthers. 



In canals, ditches, and slow running rivers. Rather scarce, but 

 o-enerally distributed in England. Common in the fenny counties. 

 Rare, and doubtfully native in Scotland, though it occurs about 

 Renfrew and other places near Glasgow. Local in Ireland, but 

 occurring in the west, centre, and north-east of the island. 



Eno-land, [Scotland,] Ireland. Perennial. Late Summer, 

 Autumn. 



Rootstock a small corm emitting elongated runners, which produce 



