*A , [ *36 J
R U P P I A maritima.
Sea Ruppia.
7 E 7 R A N D R I A Tetragynia.
G e n . C h a r . Cal. none. Cor. none. Seeds 4 , on
fo ot-fta lk s .
Spec. C har...................
S y n . Ruppia maritima. Linn. Sp. PI. 18 4 . HudJ. FI.
An. 77. With. Bot.-Arr. 177.
Potamogiton maritimum gramineis longioribus foliis,
frudtu fere umbellato. Rail Syn. 134, t. 6 ,/ . 1.
Fucus ferulaceus. Ger. em. 1373, good.
A GOOD obferver may, we believe, find this curious plant
in moll of our Britilh falt-water ditches, efpecially in the latter
part of fummer, when its pedunculated feeds diftinguilh it
from all vulgar pond-weeds. Mr. E. Eorfter, jun. favoured us
with this fpecimen from a ditch by the road from Maldon to
Goldhanger, where Ray obferved it. 1
Whether the root be annual or perennial is not eafy to determine.
The Items are long and flender, round, very much
branched, clothed with alternate linear pointed leaves, which
embrace the ftem with a membranous (heath at their bafe.
Two flowers commonly ftand feflile, one a little, above the
other, on an axillary flower-ftalk, various in length, and fome-
times coiled, by means of which they alone are raifed above the
water when the pollen is ripe. The anther» are feflile, burfting
at top into two hemifpheres; the germens feem fcarcely pedunculated
before impregnation, but are afterwards raifed in a
wonderful manner from the receptacle, each on its own proper
foot-ftalk. The feeds are oval, flightly gibbous on one fide, efpecially
when young. They ripen in Auguft.
The account in Ray’s Synopfis, written by Dillenius, is incorrect
in faying the flowers (or ftamina) grow remote from the
fruit, and that the latter appears firft.
Potamogeton marinum moft refembles the Ruppia, but even
before flowering it may be diftinguilhed by its leaves for the
moft part being not fo membranous, and alfo lefs tumid, at the
bafe. We have in the Linnaean Herbarium a fpecimen from
Dr. Hope of that variety mentioned in Lightfoot (Append. 1091),
which feems to differ from ours merely in the greater length
of its fpiral flower-ftalk, poflibly having grown in deeper or
more fluctuating water. Its feeds are indeed fpotted with red,
which we have never obferved in any other fpecimen.