Physaraceae. In fact, the
structure of the sporangium is unique among the Myxomycetes.

1. PHYSARELLA OBLONGA, B. & C. Sporangium oblong, the apex re-entrant
and confluent with the summit of the columella, the base obtuse or
slightly umbilicate, stipitate, cernuous. The wall of the sporangium a
firm, yellowish membrane, covered with minute granules and with
scattered, small, yellow scales of lime; after maturity the apex is torn
away more or less irregularly from the summit of the columella and the
wall splits into a few segments, which become reflexed and are
subpersistent about the base of the sporangium. Stipe long, erect or
flexuous, the apex bent or curved, red-brown, rising from a small
hypothallus, entering the sporangium and prolonged to the apex as a
hollow tubaeform columella. Capillitium of thick, spiniform tubules
filled with lime and slender, violet threads, extending between the wall
and the columella. The tubules elongated, terete, tapering gradually
from wall to columella, containing yellow granules of lime; the threads
very slender, outwardly branched a time or two, the further extremities
connected by short, lateral branches, often furnished with minute, free
branchlets, and containing a few small, fusiform nodules of lime. Spores
globose, nearly smooth, violaceous, 7-9 mic. in diameter.

Growing on old wood, bark, leaves, etc. Sporangium commonly .8-1.0 mm.
in length by .5-.6 mm. in diameter, the stipe 1-2 mm. long; the
spiniform tubules measure 150-200 x 15-20 mic.

The abnormal forms of this species which sometimes manifest themselves
are very singular; the sporangium has a tendency to dilate, becoming
funnel-form or even salver-shaped, the stipe shortening and even
disappearing. I have a large specimen which superficially resembles some
lichen, a _Physcia_, for example; the sporangia are pressed down,
flattened out, extremely irregular, and in many places confluent; the
rudimentary stipes are hidden beneath the leafy expansions. In all the
forms, however, may be uncovered the spiniform tubules mingled with the
slender threads. This is _Trichamphora oblonga_ B. & C. _Tilmadoche
oblonga_ of Rostafinski's monograph, and _Physarella mirabilis_ Peck.

V. CYTIDIUM, Morgan. Gen. nov. Sporangium globose or rarely ellipsoidal,
stipitate; the wall a thin membrane, with an external layer of minute
granules of lime, rupturing irregularly. Stipe more or less elongated,
tapering upward and entering the spo