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ASPLENIUM TRICHOMANES. 
[ Spleenwort Hairy, or excess of hair. Asplenium 
asTrXrjvov, asplenon , a medicine to cure diseases of the 
spleen, from « negative, and splen. Trichomanes 
from Tptj, rpixos, trix , trichos , a hair, and memos , 
loose, long, from the long free hairs attached to the 
receptacles. ] 
COMMON MAIDENHAIR SPLEENWORT. 
Syn . — 'Asplenium melanocaulon , A. saxatile , Phillitis 
rotundvfolia . 
This is a diminutive and pretty fern. It grows in 
tufts in the hedge banks, and rarely in old masonry 
near Sidmouth. The fronds vary in length from 
three to twelve inches. Stalk purplish black. Pinnae 
ovate, green, slightly notched or crenate. Each one 
is traversed by a mid- vein, which gives off veinlets 
commonly divided in two, the anterior one of which 
bears the linear sorus. This sorus, linear at first, 
subsequently assumes a rounder appearance, when 
the abundant fructification causes the sori to become 
confluent, or to run one into the other, so that the 
reverse side of the pinnae are almost covered. The 
countless multitudes of seeds that issue from the 
back of a single frond of a fertile fern is something 
beyond the capacity of the imagination to estimate. 
If they all grew the whole world would soon be 
clothed in a wilderness of ferns, to the exclusion of 
every other plant. Where, therefore, any vegetable 
( or animal ) is the most prolific, the process of its 
destruction, by a very wise provision, is balanced 
with an equal pace, in order to keep it within due 
limits. Naturalists tell us that thousands of indi- 
viduals have been counted in the roes of the herring, 
the cod, the salmon, and some others, and that the 
fronds of some ferns produce their spores by mill- 
ions; and yet, as far as human observation goes, 
the sea is not fuller of these fish now than it was a 
hundred years ago, nor the earth fuller of ferns. 
It comes to this — that if the present enormous rate 
of production is only just enough to supply the 
constant demand, or the constant destruction, it is 
certain, that if fish were not produced by thousands 
