ial layer is thin,
tearing away as the plant expands, the bark or skin falling with the
mycelium. The outer coat is deeply parted, the segments, acute at the
apex, four to twenty; strongly hygrometric, becoming reflexed when the
plant is moist, strongly incurved when the plant is dry. The inner
coating is nearly spherical, thin, sessile, opening by simply a torn
aperture. There is no columella. The threads are transparent, much
branched, and interwoven. The spores are large, globose, and rough.

The plant ripens in the fall and the thick outer peridium divides into
segments, the number varying from four to twenty. When the weather is
wet the lining of the points of the segments become gelatinous and
recurve, and the points rest upon the ground, holding the inner ball
from the ground. In dry weather the soft gelatinous lining becomes hard
and the segments curve in and clasp the inner ball. Hence its name,
"hygrometricus," a measurer of moisture. The plant is quite general.

_Geaster Archeri. Berk._

[Illustration: Figure 484.--Geaster Archeri.]

Young plant acute. Exoperidium cut beyond the middle into seven to nine
acute segments. In herbarium specimens usually saccate but sometimes
revolute. Mycelial layer closely adherent, compared to previous species
relatively smooth. As in the previous species the mycelium covers the
young plant but is not so strongly developed, so that the adhering dirt
is not so evident on the mature plant. Fleshy layer when dry, thin and
closely adherent. Endoperidium globose, sessile. Mouth sulcate,
indefinite. Columella globose-clavate. Capillitium thicker than the
spores. Spores small, 4 mc. almost smooth. _Lloyd._

I first found the plant in the young state. The acute point, which will
be seen in the photograph, puzzled me. I marked the place where it grew
and in a few days found the developed Geaster. The plant is
reddish-brown and it differs from other species "with sulcate mouths, in
its closely sessile endoperidium." I have found the plant several times
in Hayne's Hollow, near Chillicothe. I found it in the tracks of decayed
logs.

The plant has been called Geaster Morganii in this country but had
previously been named from Australia.

_Geaster asper. Michelius._

[Illustration: _Photo by C. G. Lloyd._

Figure 485.--Geaster asper. Natural size.]

Exoperidium revolute, cut to about the middle in eight to ten segments.
Both mycelial and fleshy layers are more closely adhere