UNDERGROUND FUNGI OF TASMANIA. 49] 
quite absence of a peridium. G. pallidus is a fairly large plant 
for the order—up to 3-4 cm. diameter. The peridium appears quite 
absent, and the gleba, with its copious development of minute 
tortuous canals, appears like a fungus stripped of its skin. There 
is often an indication of a sterile base, and in one plant I found 
growing from a depression in the base a minute slender stem 
about 7 mm. long. There was a total absence of column running 
through the gleba ; but one could not fail to imagine a distant 
relationship to Secotium. G. seminudus has a thin, but evident 
inseparable, skin, and appears to have lost even the semblance of 
a stem. 
Among our Hymenogasters, which are all three new, there is 
much room for reflection. H. albellus is pronouncedly subter- 
ranean, with a very small sterile base, and, like its nearest neigh- 
bour, its basidia are bisforous. HH. rodwayi has a fairly developed 
sterile base, with radiating arms running towards the apex. 
H. violaceus, on the contrary, can hardly be said to be subter- 
ranean, always becoming exposed on maturity. The base is well 
developed, and in many specimens sends a process right through 
to the apex, suggesting a close relationship to Secotiwm. 
In Lycoperdacee the genus Secotiwm consists of plants standing 
in the direct line of descent between Hymenogasters and Agarics. 
Typically they are above-ground fungi, have a well-developed 
stem, a persistent trama, and permit an escape of spores by the 
peridium bursting from the stem at the base. In Tasmania we 
have two plants that stand as near the confines of the genus as 
possible. S. gunnii, Berk., is rather variable. In one extreme it 
has a well-developed stem, whose substance expands above to 
partially form the flesh of a pileus. The lower edge of the 
peridium is quite free, and connected with the stem by an arachnoid 
veil, while the tubes, though still contorted, are roughly arranged 
at right-angles to the margin, so that they assume the appearance 
of deformed gills. In this extreme form S. gwnnii could easily, 
and indeed often is, mistaken for a deformed brown spored Agaric. 
In the further extreme the stem barely pierces to the apex, the 
base is sunk round the stem, and the tubes are much conveluted. 
Secotium rodwayt departs from the habit of the genus in being 
completely subterranean unless or until accidentally exposed. It 
has in the normal state a fairly thick but very short stem which 
pierces to the apex and a deeply indented base. The spores are 
globose, nearly smooth, and colourless ; but for this it might be 
taken for a Hymenogaster with an abnormally developed stem. 
The presence of a well-developed but apparently useless stem in 
this species, and the existence of rudimentary homologous members 
in so many of the Hymenogasters, would possibly indicate, con- 
trary to generally received doctrines, a descent of Hymenogasters 
from Agarics. 
