288 THE ESSEX NATURALIST.
has pointed out), it is so dry that they propagate in exception-
ally-wet years only. As a result, ferns which may be destroyed
by agricultural or building operations or dug up intentionally,
are replaced by nature very slowly, if at all. This striking
difference in the climates of the two counties is amply sufficient
to account for the equally-striking difference in their respective
fern-floras.
Moreover, it is certain that our fern-flora of to-day, meagre
as it is, is very much poorer, in respect of both species and
individuals, than it was less than a century ago. The decrease
has been very noticeable, even within my own recollection.
Considerably less than a century ago, the Royal Fern (Osmunda
regalis) flourished abundantly in bogs at not a few places through-
out Essex.2 To-day, I doubt whether even one single plant
grows wild anywhere in the county. Or, take such species
as the Marsh Fern (Lastrea thelypteris), the Mountain Fern
(Lastrea Oreopteris), the Herring-bone Fern (Blechnum spicant),
and the Black Spleenwort (Asplenium adiantum-nigrum). When
Gibson wrote, sixty years ago, he was able to name a fair number
of localities for each of these species. Yet, to-day, though
individual plants may still linger, these are, in most cases, no
more than a miserable remnant of those which were to be found
then. For instance, in regard to the last-named, the Black
Spleenwort, I can remember seeing it not uncommonly in one
mid-Essex locality—on the bank cf a hedge beside the Parsonage
Lane, at Broomfield.3 To-day, that lane is lined by cottages
and other buildings, including a Board School, and the plant
has long disappeared. Without doubt, there are still local-
ities for it in Essex ; but, off-hand, I cannot name even one. 
Again, when I was a boy, single plants of the Prickly Fern
(Polystichum angulare) were met with not uncommonly, growing
on the. banks of ditches in Broomfield, the Chignals, Roxwell,
and throughout the district lying to the north-west of Chelmsford,
where to-day one seldom or never sees a single plant. Even
the common Male Fera (Lastrea filix-mas) which used to be fairly
common in similar situations and in woods throughout the
same district, has become very noticeably scarcer within my
own recollection.
2 See, for example, Essex Naturalist, xix. (1921), p. 269.
3 I have a note that, on 26 December 1876, I saw "a large quantity" there, together with
a few plants of Polystichum aculeatum.