covering tlie roof of a large cavern at P e tit Bot Bay, in the
Island of Guernsey, and the specimens which he obtained there
ai-e of enormous size. Its growth is equally luxuriant in the
islands of Madeira and Teneriffe, as I have been informed by
the late Mr. W. Christy, whose ardour in botanical pursuits was
only equalled by the kindness of his heart, and whose early
loss will long he felt hy a large circle of admiring friends. Did
I need such an assistance to my memory, this fern would always
remind me of him, for it was on the occasion of our last interview,
that he described to me its beautiful growth in the island
of Madeira, and offered me the fronds he had gathered there.
In Cornwall, A. marinum grows to a larger size than in om-
northern counties, and its form, as shown below, is more elongate
and divided.
The figure in the preceding page is from a plant I gathered at
Red Noses, near Liverpool, where I regret to say that the species
has been nearly exterminated. In walking under Turk Mountain,
on my way from
Killarney towards Ken-
mare, I found this fern
in considerable abundance
to the left of the
road, on a rock which
appeared to have been
blasted but a few years
hack. The largest
plant I found was of the small size and unusual form represented
in the annexed cut, which I thought worth giving as a
record of this completely inland habitat. The plant grows at a
considerable height on the cliff, and, except to a practised eye,
would have much the appearance of Ceterach officinarum.
The root of A. marinum is black, wiry, tough, long, and so
firmly fixed in the crevices of rock that it cannot be eradicated
without the greatest difficulty ; the rhizoma is nearly spherical,
black, and covered with bristly scales : the fronds make their
appearance in June and July, ripen their seed in October, and
remain green throughout the year ; in July and August fronds
of successive seasons may he found equally vigorous.
The frond is linear, and simply pinnate : the pinnae are stalked,
ovate, and serrated ; two larger ones frequently occur near the
apex ; the pinnæ are connected hy a narrow wing ruiming along
the rachis, as shewn in the figure of the Cornish plant in the
preceding page, the upper left hand figure representing a portion
of the rachis.
The lateral veins are forked almost immediately after leaving
the midvein ; the anterior branch hears an elongate linear mass
of rust-coloured thecæ, which, when young, is covered hy a
white membranous indusium of the same shape as the mass, and
always opening towards the apex of the frond.
Adiantum trapeziforme of Hudson, Bolton, Berkenhout, &c.
I believe to be nothing more than the Cornish form of this
species. H
iiV!U