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the frond. Many sporangia are imperfectly formed, and the
spores are very rare ; — both Mr. Faxon and I have searched
many fronds, and found very few spores, which however
were ovoid-reniform and minutely roughened. Milde’s experience
is similar, and he thereupon argues the possibility
of this fern being a hybrid, though in his latest writings
he considers it a variety of A . cristatwn. '
Soon after the early fertile fronds, at the same time,
but from small side-branches of the root-stock, are produced
much smaller sterile fronds, the segments of which are less
distinct, more confluent, and less deeply toothed. Later in
the season, another set of fronds is produced, intermediate
in size and outline, but with pinnatifid pinnæ and oblong
obtuse confluent segments more like the fertile fronds of A .
cristatum. These fronds may be either fertile or sterile. The
spring fronds decay in the late autumn, but those of the
late growth remain green till late in the winter. All this is
clearly pointed out by Mr. Moore, and my own observations
confirm his remarks.
■ “ It is remarkable that the spores o f the numerous specimens I have examined
were either colorless and without contents, or black, as if carbonized, and that the sporangium
itself was often filled with only a shapeless dusty mass.” (Nov. Acta. Acad. Nat.
Cur. xxv i., ii., p. 536}—“ Of this plant I have seen so many specimens, that I may justly
contend that it is in very truth intermediate between A . cristatiim and A . spinulosum, so
that the first passes gradually into the second, and no absolute distinctions may be found
between A . cristatum and A . spinulosum.” (F il. Eur. et A tl., p. 13 1 .)
Hooker, in “ British Ferns,” has referred A . Boottii to
Nephrodium remotum, Aspidium remotum of A. Braun. In
“ Species Filicum” it is not noticed, and in “ Synopsis F ilicum”
it is made a variety of N. spinulosum.. Mr. Davenport
is disposed to consider A . remotum and A . Boottii as identical,
although Milde kept them apart and apparently had no
suspicion of their identity. Mr. Davenport remarks that a
specimen in the herbarium at Cambridge, marked A . remotum
probably by Braun himself, is so like A . Boottii that “ if detached
from its sheet and sent out for that fern it would be
generally received without question.” I have only a cultivated
specimen of A . remotum from the Leipsic garden, sent
me several years ago by Dr. Mettenius. In this frond the
pinnæ and pinnules are much like those of A . Boottii, but
the frond is scarcely narrowed at the base, and the large indusia
are wholly glandless. Milde says of A . remotum\—
“ The illustrious Braun now considers this plant a form o f ^ .
/ nevertheless I venture to defend the old opinion
and consider it a hybrid between A . Filix-mas and A . spinulosum.
If A . remotum were really nothing b u ta form of A .
Filix-mas, it is hard to understand why this form is not more
frequently observed in Germany, where A . Filix-mas is so very
common. In Silesia, where A . Filix-mas is a common plant, I
have hitherto in vain sought for A . remotum. But A . remotum
is perfectly intermediate between A . Filix-mas and A . spinu-
If hybridity among ferns be admitted, then it would apl
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