lime.

_b. Aethalium naked, i. e., without a common cortex._

2. FULIGO VIOLACEA, Pers. Plasmodium a soft effused mass, dark red or
wine-colored. Aethalium large, pulvinate or effused, orbicular or more
or less elongated and irregular, the surface minutely pitted and
perforate, furnished with a scanty layer of lime, whitish or yellowish
to brick-red in color, leaving naked purple and violet spots and
patches, seated on a thin membranaceous brick-red hypothallus. Sporangia
long, narrow, and sinuous, closely packed together; the walls a thin
violaceous membrane, rugulose and iridescent, with scattered granules,
or nearly destitute of lime. Capillitium of slender violet tubules,
forming a loose net-work, with slight expansions at the angles; the
tubules with numerous rather large vesicular expansions, ellipsoid or
fusiform in shape, and scantily furnished with lime. Spores globose,
nearly smooth, pale vinous, 6-8 mic. in diameter.

Growing on old trunks in woods; not uncommon in this region. Aethalium
1-3 or more centimeters in extent, and 5-10 mm. in thickness. The
vesicles of the capillitium vary from 15-30 or sometimes to 50 mic. in
diameter, their inner surface is usually coated by a single layer of
granules of lime, they are rarely filled with lime and sometimes are
naked entirely; when dry many of them are to be found collapsed.

3. FULIGO FLAVA, Pers. Plasmodium effused lemon-yellow. Aethalium mostly
effused, irregular, the surface reticulate, pitted and perforate,
entirely naked, pale yellow to lemon-yellow and greenish-yellow, the
hypothallus thin or scarcely evident. Sporangia laterally much
compressed, flexuous, and gyrose, not everywhere grown together, but
forming a dense reticulum; the walls a thin, pellucid membrane, with a
dense layer of lemon-yellow granules of lime. Capillitium of short and
very slender tubules, sparingly branched and scarcely forming a
net-work, not expanded at the angles; the tubules very scantily
furnished with lime, in scattered, small, fusiform nodules, white or
lemon-yellow. Spores globose, very minutely warted, violaceous, 7-9 mic.
in diameter.

Growing on mosses, old leaves, sticks, etc.; not common. Aethalia in
irregular patches 2-4 cm. or more in extent, sometimes almost reduced to
a simple plasmodiocarp. This species furnishes a clear notion of the
structure of the aethalium in the other species, on account of the
sporangia being but loosely compacted and not entirely gro