THE BRITISH PEPPERWORTS.
T h e group of plants to which the name of Pepperworts has
been given, is technically called Marsileacece, and contains
but a few genera, these being of very curious structure. It
has only two representatives in the British flora. These two
plants belong to different genera, and are both submerged
aquatic plants of small size, agreeing in having grassy or
quill-like foliage, but differing materially in habit, the one
being a creeping grower and the other tufted; the fructification
also presenting some material differences. Isoetes
is sometimes classed with the Club-mosses instead of the
Pepperworts.
Genus XX. ISOETES.
Isoetes, which takes its scientific name from the Greek
words isos, equal, and etos, the year, from its retaining its
fronds throughout the year, is commonly called Quill wort.
The genus differs from Pilularia, its nearest ally, and with
which it is associated in the order of Pepperworts, in having
