Polygonum.] polygonace^. 435 



the specimens {rathered at Freshwater Gate the fruit partakes in character both of 

 P. aviculare and that species, being considerably exserted, as in P. Rail, but 

 finely punctate or striate, under a lens of modeiate power, as in P. aviculare, yet 

 with considerable glossy lustre. Whoever will read attentively Mr. Babington's 

 account in the Suppl. to E. B. will perceive how much ambiguity attaches to the 

 discrimination of these two species of a genus so notoriously variable as the 

 present. 



*** " Styles 3. A chene triquetrous. Stem erect, twining, with ci/mose branches." 



—Br. Fl. 



8. P. Convolvuhis, L. Climbing Buckwheat. Black Bindweed. 

 Vect. Lily.* " Leaves cordato-sagittate, stem twining angular, 

 segments of the perianth bluntly keeled (rarely winged), fruit 

 opaque striated with minute points." — Br. Fl. p. 355. E. B. t. 

 941. 



/3. Segments of the perianth distinctly winged. 



In corn aud other cultivated fields, gardens and waste ground ; a troublesome 

 weed; also in moist hedges and thickets, not uncommonly. Fl. July— Septem- 

 ber. 0. 



/?. Running up pea-sticks in the garden of Williams's at Shanklin. On the 

 Dover, Ryde, Wm. Wilson Saunders, Esq. .'.'.' 



Root slender, branched. Stem slender, much branched, climbing to the length 

 of several feet upon hedges and bushes, or trailing on the ground in open situa- 

 tions, twisted, roughish and sharply angular or furrowed. Leaves alternate on the 

 lower portion of the stem, 2, 3, or 4 together under the flowering branches, cor- 

 dato-sagittate, their lobes acute, dark green, taper-pointed, thin, sometimes near 

 the sea a little fleshy. Flowers greenish or reddish, in remote subverticillate clus- 

 ters of 4 — 6 or more, on the short lateral branches, which thus become leafy 

 racemes, finally much interrupted by the elongation of the common axis; lower- 

 most clusters with a single leaf under them, upper ones leafless or nearly so, all 

 enclosed in a short sheathing bract. Pedicels smooth, jointed near the flower, 

 elongated and deflexed in fruit. Segments of the perianth very obtuse, greenish 

 at the back, broadly edged with white, three alternate ones larger, enveloping and 

 in fruit almost concealing the three inner and smaller segments, and having a 

 white keel down the centre of each, very inconspicuous in a., much broader and 

 more distinct in /3. Stamens 8 (or sometimes 6, Sm.), a little connivent; anthers 

 bright purple, with a rounded granulated protuberance at the back between iheir 

 very flat lobes ; poWera white. (Sf^Ze^i extremely short, closely united (sometimes 

 only 2, 8m.); stigmas roundish. Seeds brownish black, opaque and without 

 polish, more or less acutely triquetrous, rough with short stris or ridges disposed 

 lengthwise. 



The var. ^. is remarkable as uniting to the habit and general aspect oi P. Con- 

 volvulus much of the character of P. dumetorum, and thus strengthening the sus- 

 picion of Wahlenberg (Fl. Suec), that this latler is but a woodland form of the 

 more common species. The perianth is almost as broadly winged as in my spe- 

 cimens of the true P. dumetorum from Wimbledon in Surrey, liut the wings do 

 not taper down so decidedly into the pedicel, and though it agrees with P. dume- 

 torum in the elongation of the racemes, the somewhat greater length of the flower- 

 stalks thau is usual in P. Convolvulus, and the very distinct whorls of from 5 to 

 10 or more flowers, it has not the slender and graceful appearance of that species. 

 The fruit in our present variety is precisely the same as in the common Ibrm, 

 except that the faces of the seed are deeply concave, with 3 sharp ridges between 

 them, an appearance dependant on the imperfect development of albumen in the 

 seed, and which cannot therefore be assumed as an absolute character. The stem 

 is angular, and the leaves are of a thicker texture than in P. dumetorum, in which 



* And over the whole county. 



