NAIADACEZ. Si 
of bracts. Filament at first short, afterwards lengthening to a greater 
or less extent; anthers 2- or 4-celled. Nuts 2 to 6 together, brownish- 
olive, on a very short peduncle, subcylindrical, incurved, + inch long 
(including the beak); beak or persistent style about half the length of 
the rest of the fruit; stigma large, suborbicular, and slightly undu- 
lated at the margins. Plant pale pellucid green, turning blackish in 
drying. 
Reichenbach’s figure of Z. major, “ Bonninghausen,” is the nearest 
of those he gives to our common British plant, but is larger than I 
have ever seen it, and has the nuts much less spreading; so I do not 
venture to adopt his name for our sub-species, as Mr. Hartman 
does. 
The form I found in Swanbister Loch, Orkney, is perhaps a distinct 
sub-species; it has the beak 4 the length of the nut, which has a 
scarious entire wing on the inner margins, and a broader crenulated 
one on the back, but much narrower than in Z. pedicellata. The nuts 
are divaricate, so it is not Z. polycarpa, Nolte. 
Common Horned Pondweed. 
French, Zannichelle des mdrais. German, Kurzgestielte Zannichellie. 
Sus-Srecies (?) I.—Zannichellia pedicellata. ries. 
Prats MCCCCXXVI. 
Reich. Ic. Fl. Germ. et Helv. Vol. VIL. Tab. XVI. Fig. 21, 
C. pedunculata, Reich. 1. c. p. 22. 
Nuts distinctly pedicellate, spreading, with a winged crenulate- 
dentate keel on the back; beak as long as the rest of the fruit. 
Tn brackish ditches. Frequent in England, and probably in Ireland, 
as it is said to grow near the sea. I have seen no Scotch specimens. 
England, Ireland. Annual or Perennial. Summer, Autumn. 
Similar to the preceding, but usually larger and more branched. The 
nuts are larger, paler coloured, on conspicuous pedicels, and with a much 
longer beak; the upper or inner margin with a very narrow entire 
wing or raised line, the back with a broad membranous wing decurrent 
on the pedicel, and denticulated, with a tubercle or point given off 
from the body of the nut running into each denticulation. The pe- 
dicels are commonly about two-thirds the length of the nut, and as 
long as the common peduncle. 
I cannot find that the length of the stamens and the number of cells 
of the anthers are sufficiently constant to warrant their employment 
as specific characters, as proposed by M. Gay. 
Stalked-fruited Horned Pondweed. 
French, Zannichelle pédonculée. German, Langgestielte Zannichellie. 
VOL. Ix. I 
