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HISTOHY OF BRITISH FERNS. 
Genus X. BLECHNUM, or HAED EEEN. 
English botanists are not agreed whether this plant 
should be considered to belong to the genus Blechnum or 
Lomaria, We think it most nearly r^ated to the former, 
although in the contraction of its fertile fronds it approaches 
very near to the latter. Among the British ferns, the one 
species of this genus is known by having its fructification 
extended longitudinally on the pinnge, so as to form a 
linear or continuous sorus on each side the midvein, and 
about midway between it and the margin. No other 
British Fern has its fructification in extended lines lying 
parallel with the midrib except the Pteris, or Bracken, in 
which, however, the sorus is on the margin, and not within 
the margin and near the midvein, as in Blechnum. The 
Blechnum may, however, be at once known from the 
Pteris, by the division of its fronds, wdiich are merely 
pinnate, w^hile those of Pteris are decompound. 
The name Blechnum is an adaptation of the Greek 
hlechnon^ which signifies a Fern. There is but one native 
species, for which the specific name Spicant has un- 
questionably the right of priority over boreale^ which is 
