enerally plasmodiocarpous white,
nearly smooth; peridium more or less testaceous not scaly, but breaking
irregularly; capillitium densely calcareous, the nodules angular,
branching, sometimes united to form a pseudo-columella; spores dusky
violaceous, rough, 10-12 mu.

Sommerfeldt's description quoted by Fries, _l. c._, evidently concerned
a less calcareous phase. Fries by his annotation relieves somewhat the
reader's uncertainty.

Rostafinski calls this a badhamia but describes a physarum, and the form
has, as is believed, been consistently confused with _P. cinereum_ by
every student of the group from the days of DeBary until now. In the
second edition of the _Mycetozoa_, Lister clears the situation by
transferring the species to _Physarum_, and calling attention to
spore-dimensions. The fact is, the species in external appearance so
much resembles _P. cinereum_, that the unaided eye cannot distinguish
one from the other. Curiously enough, Rostafinski describes the form he
had before him as "one of the rarest." Doubtless had he gone back to his
specimens of _P. cinereum_ he had found plenty, for in Europe it seems
abundant everywhere. In this country it is _P. cinereum_ as now defined,
that is rarer, although not uncommon. From all connection with
_Badhamia_, as representing _B. panicea_ it should, as would appear, be
withdrawn once for all.

4. PHYSARUM SINUOSUM (_Bull._) _Weinm._

PLATE VIII., Figs. 6 and 6_a_, and PLATE XIX, Fig. 15.

1791. _Reticularia sinuosa_ Bulliard, _Champ._, p. 94; t. 446, Fig. 3.
1796. _Physarum bivalve_ Persoon, _Obs. Myc._, I., p. 6; t. III.,
Fig. 2.
1828. _Physarum sinuosum_ Wein., Fries _teste, l. c._
1828. _Angioridium sinuosum_ Grev., _Scot. Crypt. Fl._, 310.
1829. _Physarum sinuosum_ Fries, _Syst. Myc._, III., p. 145.
1875. _Physarum sinuosum_ (Bull.) Rost., _Monograph_, p. 112.
1892. _Physarum sinuosum_ Rost., Massee, _Mon._, p. 305.
1894. _Physarum bivalve_ Pers., Lister, _Mycetozoa_, p. 57.
1896. _Angioridium sinuosum_ (Grev.), Morg., _Cin. Soc. Nat. Hist._,
p. 75.
1899. _Physarum sinuosum_ (Bull.) Wein., Macbr., _N. A. S._, p. 28.
1911. _Physarum sinuosum_ Wein., Lister, _Mycetozoa, 2nd ed._, p. 76.

Sporangia distinct or plasmodiocarpous, the plasmodiocarp creeping in
long vein-like reticulations or curves, laterally compressed; sometimes
distinct and crowded, always sessile. Peridium double; the outer thick,
calcareous, fr