g contrast of color between sporangia and stipes renders this
species at sight, quite distinct from any related form. The peridia in
the specimens before us are black or iridescent-black sprinkled more or
less profusely with orange lime granules which sometimes cover all but
the base. The stipe, springing from a small hypothallus, is dark red
below for about one-fourth its height, then vermillion, above expanding
slightly beneath the peridium; the columella scant or none. The
capillitium is an elegant delicate net, with numerous small, uniformly
regular, calcareous nodes, orange; by transmitted light, yellow. The
spores, brown in mass, are, by transmitted light, pale violet, slightly
papillose, 8-10, mostly about 8 mu. The plasmodium is probably yellow.

This species is no doubt related to _P. psittacinum_. It is, however,
much smaller, has a calcareous stipe, and a much less variegated
peridium, and generally a small columella.

It is also akin to _P. globuliferum_ and to _P. murinum_, _P. petersii_
Berk. & C. is reported the same thing.

26. PHYSARUM PENETRALE _Rex._

PLATE XV., Figs. 6, 6 _a_.

1891. _Physarum penetrale_ Rex., _Proc. Phil. Acad._, p. 389.
1899. _Physarum penetrale_ Rex., Macbr., _N. A. S._, p. 55.
1911. _Physarum penetrale_ Rex., List., _Mycetozoa, 2nd ed._, p. 36.

Sporangia scattered, erect, stipitate, generally ellipsoidal, pyriform,
rarely globose; peridium membranaceous semi-transparent, studded
sparsely with rounded, pale yellow or yellow-gray lime-granules,
rupturing to the base into two or four segments; stipe variable,
slender, subulate, rugulose, flattened laterally toward the base,
translucent, dull red or golden red in color; columella four-fifths the
height of the sporangium, concolorous with the stipe, acuminate;
capillitium dense, persistent, the nodes frequently calcareous, rounded,
yellow; spore-mass brown, spores nearly smooth, brownish, 6-7 mu.

Readily recognizable by the elongate sporangia and the lengthened
columella unique among physarums. The capillitial nodes are at first
pale yellow, but tend to whiten on exposure. The spores when highly
magnified show delicate spinulescence.

Maine, New York, Pennsylvania, Ohio, Europe, Java.

27. PHYSARUM LUTEO-ALBUM _Lister_

1904. _Physarum luteo-album_ List., _Jour. Bot._, XLII., p. 130.
1911. _Physarum luteo-album_ List., _Mycetozoa, 2nd ed._, p. 48.

Sporangia gregarious, sub-globose, large, about 1 mm. in