GIORIDIUM. Plasmodiocarp laterally compressed, splitting regularly
into two valves.

2. CIENKOWSKIA. Plasmodiocarp terete, elongated, irregularly dehiscent.

3. LEOCARPUS. Sporangia subglobose or obovoid, stipitate or sessile.

_B. Outer surface of the sporangium invested with granules of lime._

_a. Stipe prolonged within the sporangium as a columella._

4. PHYSARELLA. Sporangium oblong, stipitate, the apex re-entrant.

5. CYTIDIUM. Sporangium globose, stipitate, the apex convex.

_b. Stipe never entering the sporangium._

6. CRATERIUM. Sporangium obovoid to cylindric, stipitate.

7. PHYSARUM. Sporangium globose, depressed globose or irregular,
stipitate or sessile.

8. FULIGO. Aethalium a compound plasmodiocarp.

II. Tubules of the capillitium with the granules of lime in them
distributed throughout their entire length.

9. BADHAMIA. Stipe not prolonged within the sporangium as a columella.

10. SCYPHIUM. Stipe entering the sporangium and prolonged within it as a
columella.

I. ANGIORIDIUM, Grev. Plasmodiocarp laterally compressed, more or less
elongated and flexuous, attached by the lower margin to the substratum,
and, at maturity, regularly dehiscent along the upper margin by a
longitudinal fissure; the wall a firm membrane, with the granules of
lime forming a reticulate layer on the inner surface. Capillitium a
loose, irregular net-work of tubules, extending from side to side, and
containing large, irregular nodules of lime. Spores globose, violaceous.

A genus readily distinguished by its laterally compressed plasmodiocarp,
splitting lengthwise by a regular fissure. The wall is a single
membrane, and there is but a single reticulate layer of lime upon it,
which is plainly on the inner surface.

1. ANGIORIDIUM SINUOSUM, Bull. Plasmodiocarp laterally compressed and
very much flattened, more or less elongated and flexuous, sometimes
confluent and branched or reticulate, without any hypothallus; the wall
a more or less thickened and brownish membrane, the inner surface coated
with a dense reticulately thickened white layer of lime, and often
studded with the white nodules. Capillitium of hyaline tubules, forming
a loose irregular net-work, with numerous broad vesicular expansions
filled with lime; the nodules white, very large, irregularly lobed, and
branched. Spores globose, very minutely warted, violaceous, 8-10 mic. in
diameter.

Growing on old leaves, sticks, mosses, etc. Plasmodiocarp commonl