DISPERSAL IN CUP FUNGI
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Some Cup Fungi have descended into the waters, others
have gone to earth to produce truffles and their like. A
distinct step in this direction is found in the genus.
Sepultaria. S. sepulta is to be found in sandy soil under
Cedar trees. At a late stage in its development the fruit-
body is spherical, about 5 cm. in diameter, hollow, and
occurs just below the soil level. However, at maturity it
opens at the top and pushes the soil aside so that an opening
is formed through which the spores are discharged, thanks
to the phototropism of the asci, into the outside air (Fig.-7).
It is rather a difficult fungus to find, because all that is
visible is the small opening leading to the hymenium. Genea
may be considered as illustrating the next step downwards.
This is completely hypogeal, but its apothecial construction
is still quite apparent. The cup of the apothecenium is
almost closed (Fig. 7). The hymenium is composed of
Fig. 7. Possible method of evolution of a hypogeal Discomycete.
cylindrical asci each containing in a single row, eight warted"
spores. There are paraphyses, too, but these overtop the
asci and then branch and intertwine to form a solid tissue.
The asci never burst to liberate their spores. Presumably,
as with truffles generally, dispersal is by rodents which grub
up the apothecia and eat them. In more thorough-going