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NOTKS ON PONDWEEDS. 137
G. S. PULViNARE. ]\I((sdf'rallit( pulcinaris Eclib. f., in Gard.
Cliron., 1880, i. p. 200.—Columbia ?
7. S. PUNCTATUM, Masdevallia j^unctnta Rolfe, in Gard. Chron.,
1888, ii. p. 323. — New Granada ? Closely allied to S. swertice-
J'uiium.
8. S. swERTi^FOLiuii. MaadevolHa sivertmfolia Rchb. f., in Gard.
Chron., 1880, ii. p. 390. Discovered by Lehmanu on the Western
Cordillera of New Granada.
9. S. vEEEUcosuM Pfitzer, in Engl, and Prautl., Natiirl. Pflanzenfam.,
i. Orch. p. 139. Masdevallia verrucosa Ptclib. f., in
Linna^a, xxii. (1849), p. 819. Pleurnthallis verriicosa Pichb. f., in
Bonplandia, ii. (1854) p. 24. —New Granada, near La Baja, in the
province of Pamplona, at 8200 feet elevation, Funck and Schlim,
No. 1439.
NOTES ON PONDWEEDS.
By Alfred Fryer.
PoTAMOGETON DECipiENS Nolte. Ilootstock Striking deeply into
the soil with strong far-spreading stolons ; stem stout, round,
simple below, sparingly branched above the middle ; all the
branches spreading ultimately at the surface of the water, with
widely diverging branchlets. Leaves all submerged, semi-amplexicaul,
or npper sessile; alternate, opposite at the base of the peduncles
only ; lowest leaf very rarely reduced to a short strap-shaped
phyllode which is rounded at the tip and mucronate, or with a
narrow lamina attenuated towards each end. Ordinary leaves all
similar, oblong, strap- shaped, rounded and mucronate at the apex,
or narrowed and apiculate, upper rarely orbicular, flat, or involute
at the base, sometimes longitudinally folded and recurved, with 3
princii)al ribs on each side of the midrib, the two outer sprijii/iv;/
from the base of the leaf, the inner from the midrib itself, with fainter
intermediate ribs connected by numerous conspicuous transverse
veins. Stipules blunt, stout, long ; those on the upper branchlets
longer than the internodes ; herbaceous, persistent ; those at the
base of the stem sometimes dilated towards the tip into a leaf-like
lobe, those at the base