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34 A MONOGRAPH OF THE GENUS PODAXIS DESV. (= PODAXON FE.).
belonging to the section Amanita. For a distance of 1 cm. from
the base the tissue is very compact, and is continued upwards as a
stout, central, cylindrical axis ; a thick peripheral portion of the
young fungus, in organic continuity with the apex of the central
axis and the basal compact portion, also remains as a protective
wall, homologous with the pileus of an agaric ; finally, the weft of
hypha between the central axis and the external wall becomes the
gleba, which in the median vertical section appears as an elongated
elliptical area on each side of the central axis, occupying the same
position as the gills in the vertical section of a young, unexpanded
agaric (fig. 2).
Contemporaneous with the above changes, the hyph^ forming
the peripheral portion of the entire fungus for a thickness of about
1 mm,, owing to gelification of their walls, have formed an external
cartilaginous coat, adnate at first to the inner, still living portion,
as in the genus Bovista. There is an absence of the sinuous cavities
bounded by well-defined tramal-plates, so characteristic of Gastroviycetes,
but from the earliest condition the gleba presents a spongelike
structure, its very irregular walls consisting of thin-walled,
sparsely septate hyphae, originating as lateral branches from the
hyphfe forming the central axis or the iuner portion of the outer
protective wall. Mixed with the colourless, thin-walled hyphae
described above are others, which originate from the hyphfe of the
axis ; these latter eventually become coloured, and form the capil-
litium. The thin- walled colourless hyph« forming the irregular
walls of the gleba send into the interstices numerous long, lateral
branches ; these branches—the ascogenous hyphae—are aseptate,
have very thin colourless walls, are richly supplied with granular
vacuolated protoplasm, average about 6 /x in diameter, and at the
tips produce two or more short branches, which in turn emit short
secondary branches, the whole forming a compact tuft ; these
terminal branches differ from the parent hyphae in being broken up
into numerous short cells by transverse septa ; each component
cell produces a lateral outgrowth, at first papillaeform, then
cylindrical, and eventually broadly obovate, and attached to the
parent cell by a narrow neck ; these terminal cells,—the asci,
after receiving all the protoplasm from the parent cell, are cut off
from the latter by the formation of a septum across the narrow
basal portion, and, when fully developed, measure about 20-24 x
12-14 /x. Owing to the fasciculate arrangement of the terminal
branches, the asci are densely crowded, varying in number from
ten to fifty, or even seventy on specially vigorous heads. The asci
are developed in succession, and it is not unusual to meet with
empty shrivelled asci, others with the spores not yet differentiated,
and others quite young in the same cluster. I am inclined to
believe that the short, ascigerous branches are also produced
laterally on the aseptate hypliai, but am not certain on this point.
The asci are usually constant in form and size, but now and again
an exceptionally large one maybe seen, and sometimes one or more
lateral prominences disturbs the usual symmetry of outline. The
asci are normally monosporous, but occasionally two spores are