POLYGONUM laxurn.
Slender-headed Persicaria.
OCTANDRIA Trigynia.
Gen. Char. Cal. of 5 persistent segments. Cor. none.
St am. 5—8. Styles 2—3. Fruit a one-seeded
compressed or trigonous nut, with a lateral embryo,
and the cotyledons linear-oblong.
Spec. Char. Stem ascending or erect. Ochreae lax,
very shortly ciliated ; floral ones horned. Leaves
lanceolate, attenuated at both ends, wavy. Panicles
elongated, slender. Peduncles and petioles
glandular and scabrous. Fruit lenticular, its faces
round, pointed, smooth, one fourth shorter than'
the persistent calyx.
Polygonum laxum. Reich. Icon. t. 492. FI. Ex-
curs. no. 3696. Borr. in Hook. Br. FI. (ed. 4.)
165 note.
O u r present plant is one of those which present great
difficulty to the botanist, since it appears to be exactly intermediate
between two well-known species. On the one
hand, it has the habit of P. Persicaria, from which it is distinguished
by its glandular peduncles, very shortly ciliated
ochreae, which are horned on the upper part of the stem,
and by the fruit-bearing calyx extending beyond the n u t:
on the other side, it is very nearly related to P. lapathifo-
lium, having the same glandular peduncles and foliage, but
is distinguished by its ciliated ochreae and longer calyx.
Under these circumstances, I do not consider myself at
liberty to reduce this plant to either of those species as a
variety, but would rather consider it as forming one of a
series of very nearly related species. It is, however, not
improbable that the three may ultimately be determined to