the wall
very thin and fragile. Stipe elongated, tapering upward, entering the
sporangium as a very short or nearly obsolete columella. Capillitium
arising by a few branches from the apex of the columella, these branches
forking several times at a sharp angle, but not combined into a network,
the ultimate branchlets long and free, or only connected together at
their tips by persistent fragments of the sporangial wall. Spores
globose, violaceous.

The claim of this genus to be distinguished from Lamproderma must rest
upon the fact that the branchlets of the capillitium do not anastomose
and form a network. It is the same as the genus Orthotricha of Wingate.

1. CLASTODERMA DE BARYANUM, Blytt. Sporangium very small, globose; the
wall early disappearing, except the minute fragments which persist at
the extremities of the capillitium, and a narrow collar at the base of
the columella. Stipe very long, thick and brown below, tapering upward
to a pellucid oblong swelling, thence abruptly narrowed to the apex; the
columella extremely short, capillitium of very slender pale-brown
semi-pellucid threads, divergently forking, the ultimate branchlets
often joined 2-4 together at their tips by fragments of the sporangial
wall. Spores globose, even, violaceous, 8-9 mic. in diameter. See Plate
XI, Fig. 25.

Growing in rather a scattered way on old rotten wood. Sporangium .20-.25
mm. in diameter, the stipe .7-1.3 mm. long. _Orthotricha microcephala_,
Wingate. Blytt's species was found in Norway, Wingate's in Pennsylvania;
I have met with it several times in this locality. It is possibly more
common than it appears, as by reason of the difficulty of seeing the
minute sporangium it is passed by as some mold. Blytt's spore
measurements are 9.5-11 mic.; in some specimens I have seen a few spores
of this size, but they are abnormal.

II. LAMPRODERMA, Rost. Sporangia regular, globose, stipitate; the wall
thin and fragile, rugulose, shining with metallic tints, breaking up
irregularly and gradually falling away. Stipe more or less elongated,
smooth, brown or black in color, arising from a hypothallus, tapering
upward and entering the sporangium as a short columella scarcely
reaching the center. Capillitium of numerous threads radiating from the
columella, usually forking several times and combined into a net by
lateral anastomosing branchlets. Spores globose, brown or violaceous.

Lamproderma is distinguished by the shining metallic ti