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ISOETES 
THE Quillwort family or Isoetes contains but two 
British species. They are very unlike any other of 
the Fern group, and some botanists reject them 
altogether, but their fructification induces Hooker 
and some other authors to admit them at all events 
as very close allies. 
They are more or less aquatic plants, often found at 
the bottom of lakes, making a sort of submerged 
sward. 
QUILLWORT OR MERLIN’S GRASS. 
ISOETES LAC USER IS. 
THIS was long considered to be the only native 
species. It has erect, stout, cellular leaves, the roots 
are two or three inches in length, sometimes branched, 
and nearly transparent; these spring from the tuber- 
ous caudex, the crown of which bears the awl-shaped 
brittle, evergreen leaves. 
DURIEU’S QUILLWORT. 
ISOETES D UR I EE I. 
IT is only lately that this species has been recognised 
by botanists as truly native. Its true British habitat 
