340 
THALLOPHYTES. 
dark outer peridium, and composed chiefly of branches of hyphae running longitudinally 
upwards (Figs. 229 and 230, ip). While this differentiation is proceeding from below 
upwards, small mucilaginous areolae form at certain points in a deep layer of the white 
air-containing medulla, also proceeding from below upwards, like all the succeeding 
differentiations (Fig. 228, B, and Fig. 229). The formation of mucilage advances at 
the same time from the inner peridium inwards, and leaves round each of the muci- 
laginous areolae a border of air-containing tissue (Fig. 229), which afterwards developes, 
by the dense interweaving of its branched hyphae, into a firm envelope consisting of two 
layers, in which the mucilaginous areola lies. Each of these areolae becomes a hyme- 
nial chamber. While the centre of the Fungus is becoming changed into mucilage, 
Fig. 230. — CrKcibithitn vicl^are ; long-itudinal section through the 
upper part of the right side of the mature fructification, showing the 
course of the filaments ; for the sake of clearness the number of filaments 
has been reduced and their thickness increased. 
Fig. 231.— Longitudinal section of a nearly ripe 
fructification of Phallus impudicus immediately be- 
fore the elongation of the stalk (\ the natural size) ; 
a outer layer of the peridium ; g its gelatinous layer ; 
i inner peridium ; si the stalk of the pileus t not yet 
elongated, covered by the white honeycomb-like 
ridges ; sp the dark -green mass of spores (gleba) ; 
h hollow cavity of the stalk, filled with watery jelly ; 
n the cup in which the base of the stalk remains after 
its elongation ; x the place where the inner peridium 
becomes detached by the elongation of the stem ; 
m mycelial filauient. 
the chambers grow into lenticular bodies ; a mucilaginous point has appeared at an 
early stage on the lower and outer part of each chamber, and forms its umbilicus. 
From it a denser bundle of threads runs downwards to the peridium, the umbilical 
bundle (Fig. 229, and Fig. 230, ns)\ this is itself surrounded by a conical bag {t) 
which surrounds the bundle like a loose sheath. This sheath eventually becomes 
mucilaginous; the bundle runs upwards into the mucilaginous depression of the 
umbilicus, where it is resolved into its threads which are now more loosely connected. 
The mucilaginous tissue in the interior of each chamber disappears, leaving a len- 
ticular space similar in form to the chamber itself; and from the inner layers of the 
