Class VIII. Order III. 157 



This species is distinguished by its very long 1 , virgated, flow- 

 ering branches. Stem two or three feet high, somewhat hairy. 

 Sheaths hairy, ciliate, entire or split. Leaves on short petioles, 

 ovate-lanceolate, acuminate. Peduncles or flowering branches 

 oftr-n a foot long. Flowers small, greenish, scattered, with ge- 

 nerally five stamens. Seed compressed, tipt with the deflected 

 cloven style. Woods. June, July. Perennial. 



POLYGONUM AMPHIBIUM. L. Amphibious Polygonum. 



Stamens five, styles two, half united ; leaves ob- 

 long-lanceolate, acute, rough at the edge ; spike cy- 

 lindrical. 



Syii. POLJ-GONUX AMPHIBIUM. /3. emcrsum. MX: 



Distinct from the following species by its leaves, which are 

 generally lanceolate, though sometimes rounded at base, the 

 edges ciliate-serrulate, so as to feel rough, the veins also having 

 sometimes the same character. Stem fleshy, decumbent, root- 

 ing. Sheaths tubular, smooth, entire, the lower ones sometimes 

 ragged or ciliate. Spike solitary, terminal, at first ovate, at 

 length cylindrical. Flowers large, rose coloured. Borders of 

 ponds and ditches, growing above water. August. Perennial. 



It agrees perfectly with European specimens. 



POLYGONUM COCCINEUM. Willd. Floating Polygonum. 



Stamens five, styles two, half united ; leaves ob- 

 long, smooth throughout, lucid ; spike cylindrical. 



Syn. POLTCONUM AMPHIBIUM. a. i\(,\ans. J\Ix. 



A more perfectly aquatic species than the last, better distin- 

 guished from it by the entire smoothness of its leaves than by 

 the characters usually given. Stem rooting at the joints. Leaves 

 mostly floating, green and shining above, purplish beneath, with- 

 out hairs, commonly oblong and obtuse at both ends, some- 

 times hearted at base and snbacute. Sheaths entire, the lower 

 ones sometimes ragged. Spike terminal, ovate by the expand- 

 ing of the lower flowers first, at length cylindrical. Flowers 

 rose coloured. In deep waters. August. Perennial. 



POLYGONUM ARTICULATUM. L. Jointed Polygonum. 



Stamens eight, styles three ; spikes panicled, fill- 



