CLASS V. ORDER II. J HOLOSCIADIUM. 361 



short peduncles; the general of from three to six rays, of unequal 

 lengths; partial numerous, short, unequal. Flowers white, small. 

 General involucre of about six lanceolate segments, frequently want- 

 ing; partial of about six, as long as the umbels. Calyx limb an 

 obtuse margin. Petals roundish, ovate, with a short point, rolled 

 inwards. Stamens about as long as the petals, svith slender filaments 

 and roundish anthers. Styles very short, curved. Stigmas obtuse. 

 Fruit small, roundish oblong, similar to the last species. 



Habitat Boggy meadows and watery places. In Oxfordshire, 

 Cambridgeshire, Bedfordshire, and Nottingham meadows. Side of the 

 river Fergus, a little above the bridge Ennis, Ireland. Near Edin- 

 burgh, and banks of a pond at Fisharrow, and at Guillon Links, 

 Scotland. 



Perennial^ flowering in July and August. 



It is very doubtful if this is any more than a variety of the above 

 species. The whole plant is smaller, its branches less numerous and 

 creeping, aud the umbels are stalked, not sessile; the leaves are 

 rounder, and generally more lobed and irregularly toothed. 



3. H. inunda'tum, Koch. (Fig. 425.) least Marsh-wort. Stem 

 creeping at the base, and rooting ; leaves pinnate the submersed ones, 

 with capillary much divided leaflets, the upper wedge-shaped, cut and 

 toothed ; umbels ou short peduncles, of two rays opposite the leaves. 



Hooker, British Flora, vol. i. p. 128. Lindley, Synopsis, p. 122. 

 Sii>on inundatum, Linn. English Botany, t. 227. Sium inundatum, 

 Roth. English Flora, vol. ii. p. 58. Hydrocotyle inundatum, Smith. 

 Flora. Brit. p. 290. 



Root of long slender branched fibres from the axis of the lower 

 branches. Stem slender, round, smooth, succulent, somewhat striated, 

 varying considerably in length, from a few inches to two feet, branched 

 and leafy. Leaves alternale,on somewhat channeled footstalks, dilated 

 and sheathing at the base, where it is striated, and with a thin pale 

 membranous margin; the lower leaves, when submerged in water, are 

 repeatedly divided into long slender hair-like segments, becoming in 

 the upper part of the stem broader, at length in four or five pairs of 

 wedge-shaped leaflets, deeply cleft into narrow lanceolate segments, 

 the upper leaves with ovate leaflets, toothed and lobed, the terminal 

 one three-cleft. Umbels on short stalks, opposite the leaves; the 

 general of two rays . the partial of about six short ones. Flowers 

 small, white. General involucre wanting, partial of four or five un- 

 equal lanceolate segments. Calyx limb an obtuse margin. Petals 

 ovate, with a somewhat incurved point. Stamens on short f. lamen ts, 

 with small round anthers. Style short, curved. Stigma obtuse. 

 Fruit oblong. Carpels with five prominent obtuse pale ridges. 

 Channels with slender simple vittce. Albumen nearly round, on a 

 transverse section, but slightly flattened in front. 



