Plasmodium milk-white, watery. Plasmodiocarp long and widely effused,
anon winding, here and there reticulate, always applanate; sometimes in
form an aethalium, the peridial cortex membranous, firm, thick, and
white. Capillitium well-developed, furnished with lime. Spores
thin-walled, ellipsoidal, violaceous, plicate-rugose, 14-16 x 11-12 mu.

Not common. Found occasionally in shaded situations on piles of rotting
straw or in the woods, especially on detritus of the bracken. The spores
are many of them ellipsoidal; some are spherical; all are decidedly
spinulose, perhaps might appear plicate-rugulose when dry or shrunken.
Calcareous nodules very large and irregular, white.

Schweinitz, _loc. cit._, described this form as _Enteridium cinereum_.
Rostafinski referred it to the genus _Physarum_, but was obliged to
adopt also a new specific name, as that suggested by Schweinitz was
already in use in the genus _Physarum_. Zopf, _Die Pilzthiere_, p. 149,
founds a new genus on what seems to be the same form as here considered.
This he publishes as _Aethaliopsis stercoriformis_ Z. Massee regards the
specimens discovered by Zopf as belonging to the genus _Fuligo_, and
Lister regards Rostafinski's type as _Fuligo_, and includes Zopf's
material under the Rostafinskian species.

This has been described as properly an American form; Lister cites other
far localities.

3. FULIGO SEPTICA (_Linn._) _Gmel_.

1753. _Mucor septicus_ Linn., _Sp. Pl._ II., No. 1656 (?).
1763. _Mucor ovatus_ Schaeff., _Fung. Bav._, p. 132, Fig. 192.
1791. _Fuligo septica_ (Linn.) Gmel., _Syst. Nat._, p. 1466.
1826. _Fuligo varians_ Sommf., _Fl. Lapl. Sup._, p. 231.
1809. _Aethalium flavum_ Link, _Diss._, I., p. 42.
1829. _Aethalium septicum_ Fr., _Syst. Myc._, III., p. 93.
1875. _Fuligo varians_ Sommf., Rost., _Mon._, p. 134.
1892. _Fuligo varians_ Sommf., Macbr., _Bull. Lab. Nat. Hist. Ia._
II., p. 160.
1894. _Fuligo septica_ (Linn.) Lister, _Mycetozoa_, p. 66.
1899. _Fuligo ovata_ (Schaeff.) Macbr., _N. A. S._, p. 23.
1911. _Fuligo septica_ Gmel., Lister, _Mycetozoa, 2nd ed._, p. 86.

This remarkable and universal species presents as stated many forms and
phases. Of these five have been selected as representative.

1. Form _a._ Plasmodium yellow; cortex yellow, or
orange-brown, strongly calcareous friable; form
indefinite _F. ovata_

2. Form _b._ Cort