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38 A MONOGRAPH OP THE GENUS PODAXIS DESV. {= PODAXON FR.).
careful search, with, I believe, total absence of bias, I have not in
a single instance caught a glimpse of anything that indicated the
point of attachment of a spore at the apex of what Fischer considers
to be the basidia; the apices are absolutely smooth and homogeneous,
whereas in Geaster and several genera belonging to the Hymeno-
gastrece, where the spores are sessile on the basidia, the latter
always show clearly a scar corresponding to the point of attachment
of the spores. What I do find in the shrivelled bodies, after having
become fully expanded, is an irregular slit in the wall, sometimes
apical, sometimes slightly removed from the apex, and through this
slit I assume (but in the species under consideration have no
evidence) that the spore has escaped from the ascus. A final
objection to the basidial nature of the clavate bodies in P. card-
nomalis, in common with all the species, is the total absence of
young spores ; during the examination of material from immature
specimens, I have repeatedly noticed clusters of the spore producing
bodies in various stages of development, some very small, but in
every instance perfectly smooth at the apex; whereas in the
Gastromycetes, as a rule, the spores first appear at the apices of the
basidia as conspicuous papillae.
The ascosporous hyph^, with their clusters of asci, persist in a
shrivelled condition in all the species of Podaxis, and the spores
may usually be seen adhering in clusters to the shrivelled asci,
being held by some mucilaginous substance furnished by the partial
disintegration of the hyphse, and it sometimes happens that one or
more spores are agglutinated to the apex of an ascus in such a
position as to suggest the idea of a basidium with spores attached
to its apex ; but this idea is dispelled by further examination,
which reveals spores agglutinated, but not organically attached to
the asci in all positions, and, by their dropping away when hydrate
of potash or hydrate of ammonia is run in under the cover-glass,
the last-mentioned medium is very useful in soon causing expansion
of the shrivelled asci in old specimens.
A very remarkable modification of the already-described ascogenous
mode of spore-formation is met with in Podaxis Emerici
Berk., where the hymenial hyphfe produce at their tips, and also
laterally, short, simple branches, with very few transverse septa
this septate portion eventually gives origin to numerous obovate
cells, homologous with the asci in P. indica ; these cells, after
receiving all the protoplasm from the parent-cells, are respectively
cut off from communication with the latter by the formation of
transverse septa at the narrow basal portion, are at first colourless,
and filled with granular vacuolated protoplasm, and become
differentiated into spores furnished with one (rarely two) germpores
in the thick wall, and, while yet colourless, fall away as free
spores showing very distinctly at the narrow end, the "hilum," or
projecting scar, corresponding to the point of attachment to the
parent -cell ; the spores continue to increase in size after becoming
free, and when mature are coloured olive-brown (fig. 25).
Comparing these spores with those of P. indica, we notice that
the development is absolutely homologous up to the point of