owing to the insufficiency of the specific character given by
him, Sir J. E. Smith was induced to consider it as a variety
of R. aquatilis. For a full account of the reasons which
are believed to warrant the restoration of this plant to the
rank of a species, we must refer to a paper in the Annals of
Natural History (vol. 3. p. 225), in which the writer of
.this has also claimed the right of specific distinction for R.
fluitans, figured in our following plate.
In the present plant the stems are wholly submerged
(the flowers alone rising just above the surface of the water),
long, ascending, often branching at nearly all the joints,
except a few of the upper ones, throwing out a few long,
simple, fibrous roots from the lower joints. Leaves small,
terminating below in a short, slightly sheathing, dilated base,
which is in rare instances separated from the limb of the
leaf by a very short petiole; the limb is divided into numerous
short, rigid, terete, capillary segments, which are
2, 3, or 4 times forked, and all lie in exactly the same plane,
which has a very regular orbicular outline, and is usually
nearly at right angles with the stem and with its own sheath.
Flowers large, on round solitary peduncles. Sepals very
fugacious, concave, ovate, obtuse, with narrow, white, diaphanous
margins. Petals nearly twice as long as the sepals,
ovate, blunt, white, with a yellowish claw. Stamens
numerous. Carpels in dense roundish heads, half-ovate,
compressed, transversely wrinkled, usually glabrous or
clothed with a few' bristles, laterally tipped by the persistent
incurved style. This plant differs from R. aquatilis, t. 101, by its constantly
submersed leaves never spreading into a spherical
mass as they do in that plant (this is badly represented in 1.101.), by its half-ovate and laterally tipped carpels, those of R. aquatilis being unequally ovate and tipped with an erect
style, and most remarkably by its very different general
habit. It is usually found in still water, but appears to
flourish equally well in swift brooks and rivers, often in
company with its near allies R. aquatilis and R. fluitans, but
never showing the slightest tendency to change into either
of them. It appears to be generally distributed throughout
the country. The specimens figured were gathered at Ho-
mersfield in Suffolk, on the 23rd of June 1840, at which time
it was in full flower, although R. aquatilis had then long
passed its beauty,—the latter producing its flowers in profusion
at a time (May) when even the buds of our present
subject have not made their appearance.— C. C. B.