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NOTES ON SCOTCH PLANTS. 89
formation of the terminal obovate cells borne by the specialized
septate portions of the hymenial hyphae, then in P. indica the wall
of the obovate terminal cell is recognised as an ascus, its protoplasm
resolves itself into a spore surrounded by its own cell-wall, which
in course of time escapes from the mother-cell or ascus, leaving
the latter permanently attached in a shrivelled condition to the
mother-cell, from which it originated. In. P. Emerici the obovate
bodies become directly transformed into spores, the original cellwall
adhering to, and forming a somewhat loose investment on the
inner and thicker true wall of the spore ; as the latter increases in
size, the outer wall—homologous with the ascus in P. indica—
becomes closely adnate to the inner, coloured wall, but can be
readily separated by the application of sulphuric acid. When I first
saw the spores of P. Emerici, each with its very evident hilum or
point of attachment, I searched further for the basidia, as figured
by Fischer in P. carcinomalis, each basidium bearing four sessile
spores at its apex ; but I am convinced from repeated examinations
that in P. Emerici the spores, which are the homologues of spores
and asci combined in P. indica, fall away directly from the septate
mycelium. Now it is clear that the spores of P. Emerici cannot be
called ascospores, because they are not produced in asci or mothercells,
from which they eventually escape, and, if not ascospores,
they must in the broader sense be basidiospores, and, if so, the
sparsely septate portion of mycelium from which they originate
must be a basidium. It must not be supposed that the transition
from ascospores to
with basidiospores,
basidiospores is abrupt ; in P. Emerici mixed
characterized by the well-marked hilum, may
occasionally be seen perfectly smooth spores without any trace of a
hilum ; such spores are technically ascospores, having escaped from
the mother-cell, contrary to the rule, and it is not rare to find
spores with the outermost portion corresponding to the ascus in P.
indica, split and partly removed (fig. 26) ; in fact, there is in
P. Emerici every transition of spore-origin between what has been
spoken of as ascosporous and basidiosporous respectively ; furthermore,
I have reason to believe that in every species of Pudaxis there
is a sprinkling of spores produced as basidiospores, that is, spores
falling away with the wall of the obovate cell as a permanent
external investment, instead of escaping from this wall, which then
is considered as an ascus, as is most usual in all species, except P.
Emerici, where the reverse holds good regarding the
the two modes of spore-formation.
proportions of
(To be continued.)
NOTES ON SCOTCH PLANTS.
Py G. Claridge Druce, M.A., F.L.S.
The following notes were made on a visit lo Strath Tay in 1888,
and to Easterness, Banif, Elgin, and iioss-sliiro in 188!J. The first
visit was marred by wet weather and a backward season, which