I. Aethalioid, gyrose or irregular 53. _P. gyrosum_
II. Fructification stipitate.
1. Sporangia irregular, often convolute,
involved 54. _P. polycephalum_
2. Sporangia simple, nutant, discoidal.
_a._ Thin-walled, grey or white. 55. _P. nutans_
_b._ Vari-colored, yellow, greenish,
orange, etc. 56. _P. viride_
1. PHYSARUM SERPULA _Morgan._
PLATE IX., Figs. 6, 6_a_, and 6_b_.
1831. _Physarum reticulatum_ Alb. & Schw., Schweinitz, _N. A. F._,
No. 2295.
1885. _Physarum gyrosum_ (Rost.) Wingate, Ellis, _N. A. F._, No. 1396.
1892. _Physarum gyrosum_ Rost., Massee, _Mon._, p. 307.
1892. _Cienkowskia reticulata_ Rost, Macbr., _Bull. Nat. Hist. Iowa_,
II., 2, p. 150.
1894. _Badhamia decipiens_ Berk., Lister, _Mycetozoa_, p. 33, in part.
1896. _Physarum serpula_ Morg., _Cin. Soc. Nat. Hist._, p. 101.
1899. _Physarum serpula_ Morg., Macbr., _N. A. S._, p. 29.
1911. _Physarum serpula_ Morg., Lister, _Mycetozoa, 2nd ed._, p. 81.
Plasmodiocarp repent, reticulate, forming anon lines, circles, dots,
etc., venulose pale yellow, ochraceous, at length whitish, the peridium
thin, membranaceous, simple, fragile, but withal persistent, below
united with a hypothallus which is more or less widely produced;
capillitium rather scant, but abundantly charged with polygonal nodules
of lime, yellow; spore-mass black; the spores, by transmitted light,
violaceous, warted, globose, 10-13 mu. Plasmodium, at maturity,
greenish-yellow.
A very distinct species not likely to be confused with anything else,
although in description, so far as concerns external characters,
suggesting _Cienkowskia reticulata_. The two forms are not at all alike
when placed side by side. For details as to the difference, see the
description of the species last mentioned.
Apparently not rare in eastern United States, Pennsylvania, Virginia,
Ohio, Iowa.
In 1805, Albertini and Schweinitz, _Conspectus Fungorum_, p. 251, t. 7,
Fig. 2, described as _Physarum reticulatum_, a European form which
became the basis of Rostafinski's genus _Cienkowskia_; see under that
genus. Later, 1829, Schweinitz discovered in America a physarum-looking
specimen which he took to be the same thing, and accordingly placed in
his herbarium under this name, and entered _N. A. F._ 2295. Rostafinski
further renamed another Schweinitzian species _Fuligo muscorum_ calling
it, _Mon._, p. 111, _Physarum gyrosum_. Wingate and Rex apply in Ellis,
_N. A. F._, this latter name to No. 2295 of Schweinitz. Such a reference
is a mistake, judging from Rostafinski's descriptions and from the
description and figure of Albertini and Schweinitz (_Consp. Fung._, p.
86, t. 7, I), and by the testimony of Lister. For further concerning
Rostafinski's species, see under _Physarum gyrosum_, p. 111, _Mon._
2. PHYSARUM LATERITIUM (_Berk. & Rav._) Rost.
1873. _Didymium lateritium_ Berk. & Rav., _Grev._, II., p. 65.
1875. _Physarum ditmari lateritium_ Rost., _Mon._, _App._, p. 9.
1879. _Physarum inequale_ Peck, _Rep. N. Y. Mus._, XXXI., p. 40.
1892. _Physarum chrysotrichum_ Berk. & C., Massee, p. 300.
1894. _Physarum inequale_ Peck, Lister, _Mycetozoa_, p. 60.
1896. _Physarum lateritium_ (Berk. & Rav.) Morg., _Jour. Cin. Soc._,
p. 95.
1899. _Physarum lateritium_ (Berk. & Rav.) Morg., Macbr., _N. A. S._,
p. 33.
1911. _Physarum lateritium_ Morg., List., _Mycetozoa, 2nd ed._, p. 82.
Plasmodium scarlet. Sporangia gregarious, sessile, globose or
sub-globose, or sometimes plasmodiocarpous, yellowish or orange,
everywhere, when fresh, spotted with minute scarlet granules; the
peridium thin, more or less rugulose; columella none; capillitium
delicate, generally yellow, with nodules conspicuous, yellow or reddish;
spores violet-brown in mass, by transmitted light pale violet, minutely
roughened, 7-9 mu.
A well-marked species easily recognized by the characters cited. The
extent of lime deposit at the capillitial nodes varies; sometimes very
little. This accounts for Berkeley's generic reference. On the other
hand, Lister makes the rounded lime knots "each knot with a red centre
surrounded by yellow, round, lime-granules" diagnostic. This pied
condition does not come out in any of our specimens. The capillitium in
broken specimens soon fades, tends to white, etc.
New York, Pennsylvania, Ohio, Colorado, and south. Ceylon, Java, Brazil.
3. PHYSARUM VERNUM _Somm._
1829. _Physarum vernum_ Somm., Fries, _Syst. Mycol._, III., p. 146.
1875. _Physarum cinereum_ (Batsch), Rost., _Mon._, p. 102, in part.
1875. _Badhamia verna_ Rost., _Mon._, p. 145.
1894. _Badhamia panicea_ Rost., List., _Mycetozoa_, p. 34.
1899. _Physarum cinereum_ (Batsch) Rost., Macbr., _N. A. S._, p. 34
(in part).
1911. _Physarum vernum_ Somm., Lister, _Mycetozoa, 2nd ed._, p. 75.
"Plasmodium white." Sporangia sessile, generally 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, fragile, snow-white; the inner delicate, the dehiscence by
more or less regular longitudinal fissure. Capillitium strongly
developed with abundant white, calcareous granules. Spores smooth, dull
violet, 8-9 mu. Plasmodium pale gray, or nearly white.
Easily recognized at sight by its peculiar form, bilabiate and sinuous.
Apart from microscopic structure, perfectly described by Fries, _Syst.
Myc._, p. 145. Bulliard called it _Reticularia sinuosa_. Habitat
various, but not infrequently the upper surface of the leaves of living
plants, a few inches from the ground. The two sorts of fructification
often occur side by side, or merge into one another from the same
plasmodium. Where the substratum affords room the plasmodiocarpous style
prevails; in narrower limits single sporangia stand. The calcareous
deposit on the peridium is usually very rich and under a lens appears
made up of countless snowy or creamy flakes. Forms occur, however, in
which these outer calcic deposits are almost entirely wanting; the
peridium becomes transparent, the capillitium visible from without.
Judging from material before us, this appears to be the common
presentation in western Europe. See also No. 5 following.
Widely distributed. New England to the Carolinas, and Louisiana west to
South Dakota and Nebraska, Iowa and Washington.
5. PHYSARUM BITECTUM _List._
PLATE XIX., Fig. 16.
1891. _Physarum diderma_ Rost., List., _Jour. Bot._, XXIX., p. 260.
1894. _Physarum diderma_ Rost., List., _Mycetozoa_, p. 57.
1911. _Physarum bitectum_ List., _Mycetozoa, 2nd ed._, p. 78.
Sporangia gregarious, sub-globose, sessile or plasmodiocarpous, smooth
white or pallid, terete or somewhat compressed; peridium double, the
outer wall calcareous, free and deciduous above, recurved and persistent
below; the inner, smooth, pale purplish, more persistent; dehiscence
more or less irregular beginning at the top; capillitium of large white
nodules connected by short hyaline threads; spores generally spinulose,
violaceous brown, 9-10 mu.
As suggested by the author of this species it is properly a variety of
_P. sinuosum_; certainly is, as it presents itself in this part of the
world. Of the species last named we have compressed forms opening by
narrow fissure along their knife-edged summit, with scarce place for
capillitium at all between the approaching walls; again we have colonies
of sporangia quite terete, calcareous without, opening in fragmental
fashion at the top, displaying sometimes the thin membranous inner wall
but at length fissured and gaping as in the more usual phase figured by
authors, where the plasmodiocarp is simply compressed but not
extravagantly thin. Both types occur in the western mountains, forms
with and without calcium, fissured by wider or narrower cleft, _from the
same plasmodium_; forms bilabiate and forms opening at first to display
an inner peridium; forms globose with narrow base, but apex cleft, and
forms ellipsoidal, yet compressed, opening like the gaping of some
tiniest bivalve; did not Persoon say _P. bivalve_! all are bivalvular at
the last! Nay; but what are these? Here are some of the shorter forms
become suddenly obovate, and are actually mounted on _stipes_! Surely
variation in the same plasmodium can no farther go![22]
Not rare. Colorado to the Pacific Coast. Evidently a western-American
variation of Bulliard's European type. The latter occurs abundantly in
Iowa on the shores of Lake Okoboji; otherwise not common.
6. PHYSARUM BOGORIENSE _Racib._
1898. _Physarum bogoriense_ Raciborski, Hedw., XXXVII., p. 52.
Sporangia sessile, elongate, creeping but not reticulate, semicircular
in transverse section, sometimes globose or depressed globose; peridium
double, the outer thick coriaceous, yellow or brown, dehiscing
stellately into persistent more or less triangular reflected lobes,
remote from the thin, colorless inner wall; columella none; capillitium
feebly developed, the nodes white, large, isodiametric; spores bright
violet, smooth, 7-8 mu.
This species is not uncommon in the mountains of Colorado where it has
been taken at various stations by Bethel. It is reported from
Pennsylvania and South Carolina. Raciborski describes it from Java.
In habit it is very much like some forms of _P. sinuosum_ but differs in
the depressed, rather than compressed sporangia, and in the brown color
of the outer peridium.
7. PHYSARUM ALPINUM _G. List._
1910. _Physarum alpinum_ G. Lister, _Jour. Bot._, XLVII, p. 73.
Sporangia globose and sessile or plasmodiocarpous, dull yellow, smooth
or scaly; peridium double, the outer wall densely calcareous, separating
irregularly from the membranous inner wall; capillitium densely
calcareous, the nodes large, more or less branched, yellow; spores
purple brown, closely and minutely warted, 9-14 mu.
This species is based by its author upon a gathering made in California
by Dr. Harkness and named by Phillips who received it in England,
_badhamia inaurata_. He seems not to have described it. Since its first
appearance, the form has been found repeatedly in the Juras. Specimens
are before me from Mt. Rainier believed to be the same. The
plasmodiocarpous habit and yellow capillitium separate this from related
_P. contextum_ and _P. mortoni_.
Europe, California, Washington.
8. PHYSARUM DIDERMA _Rost._
PLATE XVIII., Fig. 9.
1875. _Physarum diderma_ Rost., _Mon._, p. 110.
1898. _Physarum didermoides_ var. _lividum_ List., _Jour. Bot._,
XXXVI., p. 162.
1899. _Physarum diderma_ Rost., Macbr., _N. A. S._, p. 30.
1911. _Physarum testaceum_ Sturgis, List., _Mycetozoa, 2nd ed._,
p. 79.
Sporangia snow-white, clustered, sessile or narrowly adnate, globose or
polygonal by mutual compression; peridium double, the outer dense,
fragile, thick, calcareous, the inner delicate, remote, translucent,
capillitium well developed, the calcareous nodules white, rounded or
angular, sometimes uniting to form a pseudo-columella; spore-mass black;
spores purplish, distinctly rough, 10-12 mu.
A beautiful and distinct species. As others in the group with which it
is here associated, it is a physarum with the outward seeming of a
diderma. It occurs in Europe, therefore it is safe to assume that
Rostafinski saw it. So well marked it is that any good description will
define it, and Rostafinski describes it perfectly, adequately.[23]
Mr. Lister having used for another species the name we here apply--see
under _P. bitectum_--referred this present form to _P. didermoides_
Rost., _l. c._ Professor Sturgis, convinced that such reference was at
least doubtful, gave to our American gatherings the distinctive name
above, citing specimens from Massachusetts, from Colorado, and from
California. Curiously enough he also includes specimens of _R.
didermoides_ var. _lividum_ List., sent from England!
Rare! Certainly rare in Europe and so far seldom seen in the United
States, though widely distributed. Specimens are before us from Ohio,
Michigan, Iowa, Oregon. No doubt the mountains of the north Pacific
coast, a region to-day almost unsearched, will yet afford the species in
abundance.
As stated Mr. Lister first applied the name _P. diderma_ to a
plasmodiocarpous form occurring in England and near _P. sinuosum_. More
lately, _Mon., 2nd ed._, p. 78, he adopts a new specific name, _P.
bitectum_ for the English specimens, and enters _P. diderma_ as a
probable synonym for _P. lividum_ R. Evidently our present form as
described above has not come to Mr. Lister's view. He says the original
type is not to be consulted.
There is really no more merit in this later comparison than in that
discarded. The species _P. diderma_ is not _P. lividum_, but stands as
originally delimited, and will, doubtless, some day yet again appear in
its own behalf upon the witness-stand of time; when, as before, a
Frenchman in DeBary's old-time haunts may rise to give it welcome,
brought back by some keen-eyed Polish student eager now in the arts of
peace, from Warsaw's shady groves.
9. PHYSARUM CONTEXTUM _Persoon._
PLATE IX., Figs. 3 and 3_a_.
1796. _Diderma contextum_ Persoon, _Obs. Myc._, I., p. 89.
1801. _Physarum contextum_ Persoon, _Syn. Meth._, p. 168.
1829. _Diderma contextum_ Persoon, Fries, _Syst. Myc._, III., p. 111.
1873. _Diderma ochroleucum_ Berk. & C., _Grev._, II., p. 52.
1879. _Diderma flavidum_ Pk., _N. Y. Rep. State Mus._, XXXI., p. 55.
Sporangia distinct, sessile, densely crowded, sub-rotund reniform more
often elongate, interwoven; peridium double; the outer rather thick,
calcareous, yellow, or yellowish white, the inner thin, yellowish;
capillitium white, containing numerous large, irregular calcareous
granules; columella none; spores deep violet, 11-13 mu, covered with
minute spinules.
This singular species occurs not rarely upon the bark of fallen twigs,
upon bits of straw or grass-stems lying undisturbed upon the ground. In
such a position the slime-mould covers, as with a sheath, the entire
substratum. The outer peridium, especially its upper part, is entirely
evanescent, our Fig. 3 shows the sporangia with upper outer peridium
wanting. Not rare in summer and autumn.
New England, New York, Pennsylvania, Ohio, Wisconsin, Illinois, Iowa,
Colorado, Oregon, Nicaragua.
10. PHYSARUM CONGLOMERATUM (_Fr._) _Rost._
1803. _Spumaria granulata_ Schum., _Enum. Pl. Saell._, II., p. 196,
No. 1419.
1803. _Spumaria minuta_ Schum., _l. c._
1829. _Diderma granulatum_ Schum., Fries, _S. M._, III., p. 110.
1829. _Diderma minutum_ Schum., Fries, _l. c._, p. 111.
1829. _Diderma conglomeratum_ Fries, _l. c._, p. 111.
1875. _Physarum conglomeratum_ (Fr.) Rost., _Mon._, p. 108.
1892. _Physarum rostafinskii_ Massee, _Mon._, p. 301.
1894. _Physarum conglomeratum_ Rost., Lister, _Mycetozoa_, p. 58.
1899. _Physarum conglomeratum_ (Fr.) Rost., Macbr., _N. A. S._, p. 31.
1911. _Physarum conglomeratum_ Rost., List., _Mycetozoa, 2nd ed._,
p. 80.
Sporangia depressed, globose, or irregular, sessile, more or less
aggregated, ochraceous-yellow, peridium double, the outer, thick,
cartilaginous, at length irregularly ruptured, and reflexed, disclosing
the more delicate, ashen-gray, inner membrane which encloses capillitium
and spores; capillitium abundant, showing large, white irregular
calcareous thickenings which are often consolidated in some sporangia
tend to aggregate at the centre; spore-mass brown, spores violaceous,
slightly roughened, 8-10 mu.
This beautiful species shows a peridium as distinctly double as in any
diderma. The outer peridium is reflexed exactly as in some species of
that genus; is yellow without, white within, and withal long persistent.
The capillitium of course distinguishes the species instantly as a
physarum. By the size of the spores it is distinguished from the species
preceding. This being a decisive specific character the synonymy prior
to Rostafinski is somewhat uncertain. The specific name adopted by the
Polish author is therefore approved, although perhaps not the earliest.
Rare. The only specimens thus far are from Tennessee and Louisiana.
11. PHYSARUM MORTONI _Macbr. n. s._
PLATE XX., Figs. 2, 2 _a_.
Sporangia gregarious, clustered but distinct, sessile small, about .75
mm., bright yellow, peridium double. The outer rough, breaking up into
comparatively few rather large deciduous scales, the inner peridium
white, calcareous, both persisting below to form a distinct cup;
capillitium lax, the nodes white, large, angular; columella none;
hypothallus none; spores distinctly rough, dark brown with the usual
purple shadow, 10-12 mu.
A very distinct little species related, no doubt, to _P. contextum_,
but different in habit. It is never crowded, shows no plasmodiocarpous
tendencies, while the outer peridium is generally deciduous except at
the base and falls in flakes.
Collected several times in the Three Sisters Mountains of Oregon by
_Professor Morton E. Peck._
12. PHYSARUM BRUNNEOLUM (_Phillips_) _Mass._
PLATE XX., Figs. 7, 7 _a_.
1877. _Diderma brunneolum_ Phillips, _Grev._, V., p. 114.
1888. _Diderma brunneolum_ Phill., Saccardo, _Syll. Fung._, No. 1292.
1892. _Physarum brunneolum_ Phill., Massee, _Mon._, p. 280,
Figs. 221-222.
1894. _Craterium pedunculatum_ Lister, _Mycetozoa_, p. 71.
1911. _Physarum brunneolum_ Mass., Lister, _Mycetozoa, 2nd ed._,
p. 63, Pl. 69, Fig. _a_.
Sporangia scattered or gregarious, but not crowded, sessile, globose or
sub-depressed; peridium double, thick, smooth or polished, yellow brown,
stellately dehiscent, the segments reflexed, white within; columella
none; capillitium dense, with nodes numerous, large irregular,
internodes thin and short; spores globose, lilac, minutely warted, 6-7
mu.
This form was first described in _Grevillea_, V., p. 114, as _Diderma
brunneolum_ Phillips. Later, students of the specimens preserved by Mr.
Phillips, concur that we have to do not with a diderma, but with a
craterium, Lister, or physarum, Massee. There seems no reason why we
should not respect the decision of Massee, whose description is here
quoted in form somewhat abridged. The peridium is about as double as in
the many physarums, not more so; the inner membrane so delicate as only
occasionally to be revealed except to scrutiny most searching. But the
appearance as a whole is as of some brown diderma; only the calcareous
capillitium abides to prevent mistaken reference.
When opened by irregular dehiscence from above, the persisting cup-like
base of the sporangium recalls _Leocarpus fragilis_; but then again the
capillitium is different.
California, Portugal; Colorado,--_Sturgis._
13. PHYSARUM CINEREUM (_Batsch_) _Pers._
PLATE IX., Figs. 4, 4 _a_, 4 _b_.
1786. _Lycoperdon cinereum_ Batsch, _Elench. Fung._, p. 249, Fig. 169.
1801. _Physarum griseum_ Link, _Diss._, I, p. 27.
1805. _Physarum cinereum_ Persoon, _Synopsis_, p. 170.
1829. _Didymium cinereum_ Batsch, Fries, _Syst. Myc._, III., p. 126.
1829. _Physarum plumbeum_ Fries, _Syst. Myc._, III., p. 142.
1875. _Physarum cinereum_ Batsch, Rost., _Mon._, p. 102, in part.
1896. _Physarum plumbeum_ Fr., Morgan, _Myx. Mi. Val._, p. 98.
1899. _Physarum plumbeum_ Fr., Macbr., _N. A. S._, p. 35.
1909. _Physarum cinereum_ (Batsch) Pers., Torrend, _Flore des Myx._,
p. 183.
Plasmodium watery white, or transparent, wide streaming on decaying sod,
etc. Sporangia sessile, closely gregarious, or even heaped, sub-globose,
elongate or plasmodiocarpous, more or less calcareous, gray; peridium
simple, thin, more or less densely coated with lime; capillitium
strongly developed, the nodes more or less richly calcareous, the
lime-knots rounded, angular; spore-mass brown, spores clear
violaceous-brown, 6-7 mu, distinctly warted.
This delicate, inconspicuous species is well defined by the characters
given. It occurs not rarely on richly manured ground, in meadows, lawns,
or even on the open prairie. The plasmodium may form rings several
inches in diameter, scattered here and there over a surface several
square feet in extent, in fruit ascending the blades of grass,
completely covering these with the crowded sporangia. The color of the
fruit is well described in the specific name; gray or ashen gray. The
spores are very distinctly papillate; in some specimens, however, almost
smooth; in few instances, rough.
Common. New England west to the Black Hills and Pacific coast.
Cosmopolitan.
The present species well illustrates the difficulty confronting the
author of to-day who, discussing a group of microscopic organisms, would
fain use the nomenclature of his predecessors, honored, but equipped
with insufficient lenses. Here is a species reported common in Europe,
observed by every mycologist there, from Micheli down, and yet awaiting
adequate description until Rostafinski in his great book, gives the
results of microscopic analysis. We are now really dealing with _P.
cinereum_ Rost; _P. cinereum_ Batsch is a compliment to certain rather
clever water-color drawings.
Rostafinski gives a long list of synonyms, none, it is believed,
represent American forms; and without taking careful thought, surely no
one would rudely disturb such honorable interment; but, in his
description the range of spore-measurement, 7-13.3 mu, gives us pause,
and raises the suspicion that possibly, in one case or another, the
sepulture were perhaps premature. The range is too great! Perhaps, in
the series offered in confirmation, small-spored forms represent one
species, large-spored, something else?
European students may decide this at their leisure. But Rostafinski
having, not without much labor, practically completed his review of the
physaroid forms had almost finished the last genus _Badhamia_, when his
mind perhaps returned, no doubt with some lingering misgivings, to the
thirteenth species in his physarum list. There were there, he recalled,
some large-spored specimens which had rather badhamioid capillitium.
The sessile physarums of Fries were also before him, those especially,
"floccis albis." Of these one shall be _B. panicea_, one _B. lilacina_
and one _B. verna_, described as having rather delicate colorless
capillitial tubes combined in a loose net, the calcareous deposits about
the enlarged intersections scanty, the spores 12.5 mu.
The description of the fructification as a whole is a condensed
statement of that which describes _P. vernum_, and all taken together
indicates some physarum. See now No. 3 preceding, p. 51.
_P. plumbeum_ Fr. belongs here. It has similar spores, the only
difference is a less calcareous peridium and more scattered habit of
fructification with more nearly regular, depressed-globose sporangia.
_P. cinereum_ Pers. as cited by Link, _op. cit._, is apparently a
badhamia, may be _P. vernum_, while P. _griseum_ is probably the present
species.
14. PHYSARUM VIRESCENS _Ditmar_.
PLATE VIII., Figs. 7, 7 _a_, 7 _b_.
1817. _Physarum virescens_ Ditmar, Sturm, _Deutsch. Fl. Pilze_, I.,
p. 123, Pl. 61.
1875. _Physarum ditmari_ Rost., _Mon., App._, p. 8.
1892. _Physarum ditmari_ Rost., Macbr., _Bull. Lab. Nat. Hist. 1a._,
II., p. 155.
1894. _Physarum virescens_ Ditmar, Lister, _Mycetozoa_, p. 65.
1909. _Physarum virescens_ Ditmar, Torrend, _Flo. d Myx._, No. 207.
1911. _Physarum virescens_ Ditmar, Lister, _Mycetozoa, 2nd ed._,
p. 83.
Sporangia sessile, crowded or heaped in small bunches, a dozen or more
sporangia in one pile, spherical, ovoid or elongate, yellow or greenish
yellow; peridium thin, fragile; capillitium delicate, with rather small,
irregular, yellowish, calcareous nodes; columella none; spores bright
violet, minutely roughened, 7-9 mu.
This species occurs more commonly on moss-tufts, with which it is
frequently con-colorless, or escaped on dead leaves, etc. The peridium
is flecked with calcareous scales or grains stained yellow or green, and
to these the whole fruit owes its peculiar color. The color and
aggregate, heaped sporangia are distinctive macroscopic characters.
In the _Monograph_, p. 113, Rostafinski adopted properly Ditmar's name
for this species. Upon later consideration, in the _Appendix_, p. 8, he
changed the name, writing _P. ditmari_, on the ground that _virescens_
was descriptive of a character to which the species in question
occasionally refuses to conform. Most authors since Rostafinski have
simply accepted his suggestion, so that the species is often entered _P.
ditmari_ Rost. _P. virescens_ is certainly to be preferred. _N. A. F._,
2692.
Canada, New England, New York, Pennsylvania, Ohio, Iowa, Black Hills,
South Dakota.
15. PHYSARUM RUBIGINOSUM _Fries_.
1817. _Physarum rubiginosum_ Fries, _Symb. Gast._, p. 21.
Plasmodium scarlet. Sporangia globose or cylindric, sessile or sometimes
narrowed to a stem-like base as if short-stipitate, olivaceous brown
with sometimes a flush of red; the peridium simple, thin rugulose or
plain, the calcareous scales few, or apparently included; columella
none; capillitium dense, the nodules rather large, angular, rusty brown;
spores dull violaceous, gently roughened, about 10 mu.
A beautiful well-marked species, but evidently rare in North America.
Our only typical specimens are from the gatherings by Mr. Wingate, part
of which is by Lister referred to this species, _Mycetozoa, 2nd ed._, p.
82.
_P. rubiginosum_ Fr. in the _N. A. S._, 1899, is based on certain west
coast specimens now known as _Badhamia decipiens_ Berk.
In Colorado there occurs a plasmodiocarpous form of the species. It has
the characteristic spore and capillitium but in form and habit differs
very decidedly. The fructification is a delicate netted plasmodiocarp,
the tubule about .5 mm., bright red; the peridium simple, cartilaginous,
dehiscent from above, and flecked with just here and there a red
calcareous scale.
Collected at Palmer Lake; _Professor Bethel._
16. PHYSARUM INSTRATUM _Macbr. n. s._
1899. _Physarum thejoteum_ Macbride, _N. A. S._, p. 36, not Fries,
as cited.
1911. _Physarum virescens_ Ditmar, Lister, _Mycetozoa, 2nd ed._,
p. 83.
Sporangia very small, closely crowded on a delicate, more or less
visible hypothallus, often connate, but not superimposed, sub-spherical,
dull orange, brownish or tawny; peridium thin, violaceous, covered with
very minute yellow calcareous scales; columella none; capillitium lax,
sometimes almost wanting; the nodules small, yellowish or brownish,
occasionally confluent; spore-mass violaceous, spores by transmitted
light, violet-tinted, smooth or nearly so, 6-7 mu.
Not uncommon in the Mississippi valley, where it sometimes is passed by
the collector as an immature form of some other species. The appearance
is very characteristic, unlike _P. virescens_ in both habit, size, and
color. Colonies are quite often three inches in length. The most common
habitat seems to be rotten oak, especially fragments of charred logs,
etc.
Ohio, Illinois, Missouri, Iowa, Nebraska.
This species presents a decidedly well-marked form, so much so that it
may be easily recognized at sight, without a lens. It therefore requires
special discussion, and although in the spore-characters and some minor
but not determinative details it agrees with _P. virescens_ Ditm. to
which it is by European authors sometimes referred, it seems
nevertheless deserving of specific recognition, since in its entire
habit and expression it is not only completely different but is constant
in its specific peculiarities, much more so than is the suggested
related form.
In the first edition of this work, the form was referred to _Physarum
thejoteum_ of Fries. This was the judgment of our American colleague,
Professor A. P. Morgan whose work in this group is widely recognized.
Fries admits, _Syst. Myc._, III., p. 142, that while he deems _P.
thejoteum_ very distinct, he yet has not seen _P. virescens_ Ditm.!
Since our form apparently does not occur in Europe, specimens which the
distinguished author had before him were doubtless representatives of
the now commonly recognized species of Ditmar.
For these reasons it seems appropriate to give the American type a
suitably descriptive title.
17. PHYSARUM MEGALOSPORUM _Macbr._
PLATE XVI., Figs. 7 and 7 _a_.
1917. _Physarum melanospermum_ Sturgis, _Mycologia_, Vol. IX, p. 323.
Sporangia gregarious, sessile, or short stipitate depressed, annulate,
or at least umbilicate above, white or anon roseate, about .75 mm;
stipe, when present, short, thick, black or dark brown! hypothallus
none; columella none; capillitium strongly calcareous, an abundance of
irregular white nodules burden the delicate net; spores dark sooty brown
with a shade of purple by transmitted light, verruculose, 12-13 mu.
This species is recognizable at once by its regular, uniform, depressed,
annulate or pitted sporangia, scattered evenly over the habitat of
rotten leaves or wood. It suggests a didymium in its form and habit, but
is near a badhamia. Colorado; _Bethel_, 1908.
18. PHYSARUM CONFERTUM _Macbr. nom. nov._
PLATE XV., Figs. 1, 1 _a_, 1 _b_.
1899. _Physarum atrum_ Schw., Macbr., _N. A. S._, p. 36.
1911. _Physarum atrum_ Schw., Lister, _Mycetozoa, 2nd ed._, p. 74.
Sporangia small about .2-.3 mm. in diameter, gregarious, confluent,
clustered or heaped, dull violaceous brown; peridium thin, more or less
transparent, generally limeless but sometimes lightly sprinkled with
minute white flecks: capillitium scanty, the calcareous nodes small,
rounded, elongate, white! columella none; spores violet-brown,
distinctly warted, 10-12 mu.
Having been assured on information believed trustworthy that the
Schweinitzian herbarium confirmed the identity of the species before us,
in the first edition of this work the form was listed as _P. atrum_
Schw. Meantime in the herbarium referred to, at Philadelphia the
original type of _P. atrum_ still exists. My valued correspondent, Mr.
Hugo Bilgram, has recently given it careful study. It is a limeless _P.
didermoides_ (Pers.) R.! Small wonder we have had trouble! Exit
_Physarum atrum_ Schw.
The species is not uncommon, especially eastward; has been generally
ignored for reasons cited.
Distinguished from everything else by the color and small size of the
heaped sporangia. It resembles some phase of _P. virescens_ where the
sporangia are small and somewhat heaped or rather aggregated, and
scantily supplied with lime; but in such case the lime is yellow and the
spores are small.
This species has also been constantly referred to our confused _P.
cinereum_, _P. plumbeum_, etc., but Schweinitz, who certainly had seen
_P. cinereum_ in Europe, since he cites it, under several forms, in the
_Conspectus_, found the species in America and proceeded in Pennsylvania
in December to find something else, very different as he thought, and in
fact. He called this new discovery _P. atrum_, "beautifully
_reticulate_", he says "like _P. cinereum_ but larger."
Most American students in an effort to keep faith with their pioneer
mycologist, have taken cue from the specific name, looking for something
_black_, heedless that in Pennsylvania almost any delicate thing has
'dark looks' in the middle of the winter! Berlese in Saccardo _Syll._
VII., p. 350, regarding _P. atrum_ as a synonym, writes for the black
American specimens, _P. reticulatum_, emphasizing another Schweinitzian
descriptive adjective. But _P. atrum_ Schw. has had place in literature
to this hour.
19. PHYSARUM MELLEUM (_Berk. & Br._) _Mass._
1873. _Dydymium melleum_ Berk. & Br., _Jour. Linn. Soc._, XIV., p. 83.
1873. _Didymium chrysopeplum_ Berk. & C., _Grev._, II., p. 53.
1876. _Physarum schumacheri_ Spr. var. _melleum_ Rost., _Mon., App._,
p. 7.
1892. _Physarum melleum_ Massee, _Mon._, p. 278.
1896. _Cytidium melleum_ (Berk. & Br.), Morg., _Jour. Cin. Soc._,
p. 83.
1899. _Physarum melleum_ (Berk. & Br.), Mass., Macbr., _N. A. S._,
p. 47.
1911. _Physarum melleum_ Mass., Lister, _Mycetozoa, 2nd ed._, p. 46.
Sporangia scattered, stipitate, globose, flattened below, clear yellow
or honey colored; stipe short, about equaling the sporangium, pure
white, somewhat wrinkled; columella small but distinct, white;
hypothallus none, capillitium abundant, open, snow-white, with rather
large angularly stellate nodes; spore-mass brown, almost black; spores
by transmitted light, pale violet or lilac-tinted, almost smooth, 7.5-10
mu.
Easily distinguished by its white stipe, columella and capillitium in
contrast with yellow peridial walls. _N. A. F._, 1395. Massee refers
this number erroneously to _P. schumacheri Rost._ The description and
specimen do not correspond. By that name the species has however, been
hitherto known in the United States.
Eastern United States, common; rare west of the Mississippi.
Reported from Brazil, Japan and the tropic islands round the world.
Portugal.
20. PHYSARUM CITRINUM _Schumacher_.
1803. _Physarum citrinum_ Schum., _Enum. Pl. Saell._, II., p. 201.
1911. _Physarum citrinum_ Schum., List., _Mycetozoa, 2nd ed._, p. 51.
Sporangia gregarious, scattered, globose, somewhat flattened below, pale
yellow, citrine, stipitate; the peridium thin, covered almost completely
with small calcareous scales; stipe stout, erect, fragile, tapering
upwards, furrowed, opaque, arising from a small hypothallus which is
anon continuous from one sporangium to the next; columella small,
conical, yellow; capillitium a rather dense, delicate network, the
calcareous nodules yellow, numerous, roundish, and generally small;
spore-mass black; spores under the lens violaceous, almost smooth, about
8 mu.
This species seems to be rare in the United States. It resembles
somewhat _P. melleum_, from which it is distinguished by its yellow
stipe. _P. galbeum_ is a smaller form, and lacks the columella.
Rostafinski strangely confused the synonymy here, including even _P.
rufipes_ Alb. & Schw.
New England, Ohio, Colorado.
21. PHYSARUM GLOBULIFERUM (_Bull._) _Pers._
1791. _Sphaerocarpus globuliferus_ Bull., _Champ._, Pl. 484, Fig. 3.
1801. _Physarum globuliferum_ Pers., _Syn._, p. 175, T. III.,
Figs. 10, 11, 12.
1829. _Diderma globuliferum_ Fries, _Syst. Myc._, III., p. 100.
1876. _Physarum petersii farlowii_ Rost., _Mon., App._, p. 6.
1879. _Physarum albicans_ Peck, _Rep. N. Y. Mus._, XXX., p. 50.
1893. _Physarum columbinum_ Macbr., _Bull. Lab. Nat. Hist. Iowa_,
II., 384.
1899. _Physarum globuliferum_ (Bull.) Pers., Macbr., _N. A. S._,
p. 45.
1911. _Physarum globuliferum_ Pers., Lister, _Mycetozoa, 2nd ed._,
p. 48.
Sporangia gregarious, stipitate, globose, or slightly depressed above,
pale blue-gray or pure white; stipe sometimes equal to the sporangium,
generally longer, slender, slightly wrinkled, white, or yellow, pallid,
when longer tapering upward; columella white, conical, sometimes
obsolete; hypothallus none; capillitium dense, but delicate, persistent,
a close network of hyaline threads, with white or yellowish nodes
sparingly thickened and calcareous, many without lime; spore-mass brown;
spores by transmitted light, violet, minutely warted, 7.5-9 mu.
Plasmodium greenish-yellow.
This species, very common eastward, rare west of the Mississippi, is at
once very beautiful and very variable. Its several phases have been
again and again observed and described too often by distinct specific or
varietal names. A form from New York, with long, white stems and almost
pure white sporangia, is _P. albicans_ Peck. Forms occur like _P.
albicans_, but flushed with _rose_ throughout. From New England,
specimens sent Rostafinski were by him deemed a variety of _P. petersii_
Berk. & C., and called _P. petersii_ var. _farlowii_ Rost. By this name
the species has been generally distributed in this country. _N. A. F._,
1120. Most gatherings of this species have small, somewhat ochraceous,
sporangia, and pale yellow, or somewhat rusty, stipes. These latter,
with somewhat heavier stem, represent _Physarum simile_ Rost. A form
collected sparingly in Iowa has short, white stipes and blue gray
sporangia one-third larger than observed in the eastern types. This was
recorded, _l. c._, as _P. columbinum_ Macbr.; name already in use. The
spores in the Iowa specimens are also a little larger, 8-10 mu. Pale
cyanic and roseate forms also sometimes occur in late fruitings; see
next species.
In all phases the persistent tenacity of the capillitium is a striking
characteristic well noticed by Fries (_l. c._, p. 101): "Peridia a gleba
omnimo libera, dein tota diffracta, evanescentia, ... capillitio
compacto forma servata persistente." The peridium, except a small part
below, all falls away, leaving the capillitium apparently intact,
crowded with spores.
From England to Iowa; Canada, south to Louisiana and Mexico; apparently,
in one form or another, cosmopolitan.
22. PHYSARUM LILACINUM _Sturgis & Bilgram._
1917. _Physarum lilacinum_ Sturg. & Bilg., _Mycologia_, Vol. IX.,
p. 323.
Sporangia gregarious, stalked, globose, erect, pale-lilac to pale
Indian-red in color, 0.5 mm. in diameter; sporangium-wall membranous,
beset with rounded masses of lilac or reddish lime. Stipe erect,
broad-based, tapering upwards, calcareous, furrowed, paler than the
sporangium or concolorous, 0.7-0.9 mm. long, about 0.1 mm. thick,
columella conical or columnar, capillitium delicate, rigid, persistent;
lime-knots small, rounded, composed of large, pale lilac, or reddish,
spherical granules. Spores pale-brown, almost smooth, 8-9 mu.
Vicinity of Philadelphia,--Bilgram.
23. PHYSARUM MURINUM _Lister_.
1894. _Physarum murinum_ Lister, _Mycetozoa_, p. 41.
1899. _Physarum ravenelii_ (Berk. & C.) Macbr., _N. A. S._, p. 48.
1911. _Physarum murinum_ Lister, _Mycetozoa, 2nd ed._, p. 50.
Sporangia scattered, globose or perfectly spherical, ashy-brown,
rugulose, stipitate; stipe elongate, pale brown, erect, generally
tapering upward, calcareous, brittle; hypothallus none; columella short,
hemispherical or bluntly conical; capillitium dense, much as in _P.
globuliferum_, the calcareous nodules, umber, brownish or orange-yellow,
small; spore-mass brown; spores by transmitted light, bright lilac,
almost smooth, 7-9 mu.
A very distinct species, easily known by its peculiar drab-colored
peridium and dull brown stalks. The author of the species allows for the
capillitial nodes none other tint but brown. Under direct illumination
many gatherings, especially where the sporangia are well blown out, show
nodules of a bright orange tint.
Not rare in the eastern United States, to Missouri and Iowa. Reported
also from western Europe.
Mr. Lister finds _Didymium ravenelii_ Berk. & C., on which _P.
ravenelii_ (Berk. & C.) Macbr. is founded, referable to _P.
pulcherripes_ Pk.
24. PHYSARUM PULCHERRIMUM _Berk. & Rav._
1873. _Physarum pulcherrimum_ Berk. & Rav., _Grev._, II., p. 65.
1875. _Physarum pulcherrimum_ (Berk. & Rav.) Rost., _Mon._, p. 105.
1879. _Physarum atrorubrum_ Peck, _Rep. N. Y. Mus._, XXXI., p. 40.
1899. _Physarum pulcherrimum_ Berk. & Rav., Macbr., _N. A. S._, p. 49.
1911. _Physarum pulcherrimum_ Berk. & Rav., Lister, _Mycetozoa,
2nd ed._, p. 50.
Plasmodium dark red. Sporangia scattered or gregarious, globose, even,
or somewhat wrinkled, dark red, stipitate; stipe cylindric, even,
sub-concolorous or blackish; columella small or none; capillitium free
from spores, whitish, with a slight pinkish tinge; spores dark brown in
mass, dark red when separated, globose, smooth, 7.5-8.5 mu.
The capillitium is very delicate, and when cleared of spores the
knot-like thickenings are seen to be very small and of a dark red color,
to which is probably due the pinkish tinge which marks the whole. A part
only of the thickenings are filled with lime granules. The dark red
granules of the sporangium walls are abundant and appear to form a
continuous crust.
This is _P. atrorubrum_ Peck, and his description, _l. c._, has been
closely followed. The very brief description in _Grevillea_, however,
antedates the New York publication and, all inadequate as it is, no
doubt applies to the same thing.
Not rare. New York, Pennsylvania, Ohio, Missouri, Iowa.
25. PHYSARUM PULCHERRIPES _Peck._
1805. _Physarum aurantiacum_ var. _rufipes_ Alb. & Schw., _Consp.
Fung._, p. 94.
1829. _Diderma rufipes_ (Alb. & Schw.) Fries, _Syst. Myc._, III.,
p. 101.
1873. _Physarum pulcherripes_ Peck., _Bull. Buff. Soc. Nat. Hist._,
I., p. 64.
1873. _Didymium erythrinum_ Berk., _Grev._, II., p. 52.
1873. _Didymium ravenelii_ Berk. & C., _Grev._, II., p. 53.
1873. _Physarum petersii_ Berk. & C., _Grev._, II., p. 66.
1875. _Physarum schumacheri_ Spr. var. _rufipes_ Alb. & Schw., Rost.,
_Mon._, p. 99.
1894. _Physarum pulcherripes_ (Peck), Lister, _Mycetozoa_, p. 41.
1896. _Cytidium rufipes_ (Alb. & Schw.) Morg., _Jour. Cin. Soc. Nat.
Hist._, p. 81.
1899. _Physarum rufipes_ (Alb. & Schw.) Morg., Macbr., _N. A. S._,
p. 50.
1911. _Physarum pulcherripes_ Peck., List., _Mycetozoa, 2nd ed._,
p. 49.
Sporangia gregarious, dark-colored, sprinkled with orange flakes of
lime, globose, the wall thin, deciduous, stipitate; stipe slender,
erect, deep red, sometimes black below, pale or orange above, and
supported on a well-developed hypothallus; columella scant or none;
capillitium dense, the meshes and nodes unusually small and delicate,
the latter reddish or yellow; spore-mass black; spores by transmitted
light, violet-tinted, 8-10 mu., almost smooth.
The striking 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 diameter,
yellow shading into white, orange or olivaceous, smooth or rugulose,
stipitate; stipe stout, smooth, .5-1 mm. high, yellow or orange above,
white below, cylindric, lime-stuffed; columella large, sub-globose or
clavate, yellow; capillitium either of very slender pale yellow,
threads, branching at acute angles and anastomosing or of broad, yellow
simple or forked strands, persistent after spore-dispersal; nodules few,
small, linear or fusiform; spores purple-brown, spinulose, 10-12 mu.
This species, originally described from England and northern Europe has
more recently been identified in material sent by Professor Sturgis from
Colorado. In description the form is well marked; evinces apparently
great variation alike in form, color, and structure.
The material we have, however, is poor, badly weathered.
The general plan of structure corresponds very well with Fries' idea of
his genus Tilmadoche, although the present species would seem, by very
grossness, strangely out of place with the tilmadoches. But the
singular, didermoid, evenly branching, threads of the capillitium,
bearing their slender spindle-shaped burdens of lime are very
suggestive; it is a diderma gone wandering into the camp of the
physarums if one may judge from Miss Lister's graphic plate.
The specific name selected for this peculiar form has once before done
service, but apparently for something quite dissimilar. Schumacher,
_Enum. Pl. Saell._ II., p. 199, has _P. luteo-album_. Fries thinks he
had a perichaena on hand; at any rate, not a physarum, and makes
Schumacher's combination a synonym for _Perichaena quercina_ Fr., which
Rostafinski in turn makes synonymous with _P. corticalis_ (Batsch) R. If
"once a synonym always a synonym" be esteemed good taxonomic law, this
species must one day have another name. The present author, unwilling to
change his colleague's preference in this case, nevertheless begs to
suggest that such a binomial as _P. listeri_ would probably at once make
future history of the species less eventful, and honor the memory of
England's latest and most distinguished student of the group he loved.
28. PHYSARUM NUCLEATUM _Rex._
1891. _Physarum nucleatum_ Rex., _Proc. Phil. Acad._, p. 389.
Sporangia gregarious, spherical, 1/2 mm., white, stipitate; peridial
wall membranaceous, rupturing irregularly, thickly studded with rounded
white lime-granules; stipe about 1 mm., subulate, yellowish-white,
rugose; columella none, capillitium dense, snow-white, with minute,
white, round or rounded nodes, in the centre a conspicuous mass of lime
forming a shining ball, not part of the stipe although sometimes
produced toward it; spore-mass black; spores brown-violet, delicately
spinulose, 6-7 mu.
This species most nearly resembles in appearance and habit of growth _P.
globuliferum_ Pers., but may be distinguished from it by the absence of
a columella, by the central ball of lime, and the very small rounded
lime-granules in the meshes of the capillitium. Exceptionally the lime
granules of the sporangium wall are sparse or absent entirely, in which
case the wall has a silvery or coppery metallic lustre.
Pennsylvania, Nicaragua.
29. PHYSARUM WINGATENSE _nom. nov._
PLATE XVI., Figs. 3, and 9.
1876. _Tilmadoche columbina_ (Berk. & C.) Rost., _Mon., App._,
p. 13 (?).
1889. _Tilmadoche compacta_ Wing., _Proc. Acad. Nat. Sci._, p. 48.
1894. _Physarum compactum_ List., _Mycetozoa_, p. 45.
1896. _Physarum compactum_ (Wing.) Morg., _Jour. Cin. Soc._, p. 91.
1899. _Tilmadoche compacta_ Wing., Macbr., _N. A. S._, p. 61.
1916. _Physarum columbinum_ (Rost.) Sturg., _Mycologia_, Vol. VIII.,
p. 4.
Sporangia gregarious, or somewhat crowded, erect or cernuous, stipitate,
gray or brownish gray, globose; peridium thin, metallic brown or bronze
in color, splitting at maturity in floriform manner into six to twelve
segments; stipe white or yellowish white, often shading to black or
fuscous below, rather long, tapering upward; hypothallus none; columella
none; capillitium extremely delicate, white or colorless, radiating from
a central lime-mass or nucleus, and with ordinary nodules small and few,
fusiform; spore-mass brown; spores by transmitted light, violet-brown,
delicately warted, 7-8 mu.
This species is well marked by several characteristics; the brilliant
wall of the peridium, white-flecked and laciniate, the delicate
_Didymium_-like capillitium running from centre to peridium, and
especially the peculiar aggregation of lime at the center of the
sporangium, like nothing else except a similar structure found in
_Physarum nucleatum_ Rex. The variations affect the stipe and the
distribution of the capillitial lime. Some eastern specimens show stipes
melanopodous, black below; specimens from Ohio and Nicaragua show stipes
milk-white throughout. As to the capillitium, in some of the Nicaragua
collections the lime is more uniformly distributed through the
capillitium, and accordingly the nucleus is not conspicuous, its place
being taken by two or three nodes plainly larger than the others. The
peculiar brown metallic lustre of the peridial wall, and the strongly
developed calcareous patches with which the peridium is covered are
constant features.
That this is the _Didymium columbinum_ Berk., or _T. columbina_ (Berk.)
Rost., is very doubtful; the specific name given by Wingate becomes
inapplicable when the series is transferred to _Physarum_, since in that
genus the combination is already a synonym. See _P. compactum_
Ehrenberg, _Syl. Myc. Berl._, p. 21 (1818), cited repeatedly in the
synonymy; Fries, _op. cit._, Vol. III., p. 101. So also _P. columbinum,
l. c._, pp. 133, 135, etc., to say nothing of the fate of Persoon's
first record, _Obs. Mycol. pars prim._, p. 5, 1796. This is Wingate's
species, let it bear his name.
30. PHYSARUM NEWTONI _Macbr._
PLATE XIV., Figs. 5, 5 _a_, 5 _b_.
1893. _Physarum newtoni_ Macbr., _Bull. Lab. Nat. Hist. Iowa_, II.,
p. 390.
1899. _Physarum newtoni_ Macbr., _N. A. S._, p. 37.
1911. _Physarum newtoni_ Macbr., Lister, _Mycetozoa, 2nd ed._, p. 54.
Sporangia simple, gregarious, short-stipitate or sessile, globulose or
flattened, when not globose, depressed and deeply umbilicate above,
purple, smooth, thin-walled, stipe when present very short and
concolorous; columella none; hypothallus none; capillitium abundant,
delicate, with more or less well-developed nodules, which are also
concolorous; spores by transmitted light, dark brown, thick-walled,
rough, nucleated, about 10 mu.
A very handsome little species collected by Professor G. W. Newton in
Colorado, at an altitude of several thousand feet. Easily recognized by
its almost sessile, rose purple, generally umbilicate sporangium.
31. PHYSARUM PSITTACINUM _Ditm._
1817. _Physarum psittacinum_ Ditm., Sturm, _Deutsch. Fl. Pilze_,
p. 125.
1829. _Physarum psittacinum_ Ditm., Fries, _Syst. Myc._, III., p. 134.
1873. _Physarum psittacinum_ Ditm., Rost., _Mon._, p. 104.
1911. _Physarum psittacinum_ Ditm., Lister, _Mycetozoa, 2nd ed._,
p. 55.
Sporangia scattered or gregarious, globose or depressed-globose, or
reniform, iridescent-blue, mottled with various tints, red, orange,
yellow, white, stipitate; stipe equal, or tapering slightly upward,
rugose, orange or orange red, without lime, rising from a small
concolorous hypothallus; columella none; capillitium dense, crowded with
calcareous, brilliant orange nodules which are angular in outline and
tend to aggregate at the centre of the sporangium; spore-mass brown;
spores by transmitted light, pale brown, slightly but plainly warted,
about 10 mu. _N. A. F._, 2492.
Differs from _P. pulcherripes_ Pk. in external coloration, the peridium
a rich blue, mottled but not with lime; in the capillitium, dense,
calcareous, with large angular or branching nodes; in the stipe without
lime; in the spores, a little larger than in _P. pulcherripes_, and by
transmitted light much more distinctly brown in color. The sporangia are
also broader in the present species, reaching 1 mm.
Rare. Maine, New York, Massachusetts, Pennsylvania. Reported common in
Europe, Ceylon, Japan, etc.
32. PHYSARUM DISCOIDALE _Macbr. n. s._
PLATE XX., Figs. 3 and 3 _a_.
Sporangia gregarious, scattered, discoidal, depressed or umbilicate
above, sometimes almost annulate, snow-white, small, .5-.7 mm.,
stipitate; stipe about twice the sporangium, pale yellow, strand-like,
but erect, even; hypothallus none; columella none; capillitium strongly
calcareous, almost as in _Badhamia_, aggregate at the center, and
forming a pseudo-columella at the base of the peridium; peridial wall
firm, covered with innate patches of lime, somewhat yellow at the base;
spores minutely spinulose, violaceous, 7-9 mu.
This little species reaches us from California. It appears in late
winter in undisturbed grass tufts and the sporangia are scattered over
the lower leaves. It displays a remarkable amount of lime. The nodules,
however, are not large; they are rounded and connected here and there by
the ordinary retal tubules characteristic of a physarum.
33. PHYSARUM LEUCOPHAEUM _Fr._
1818. _Physarum leucophaeum_ Fr., _Symb. Gast._, p. 24.
1875. _Physarum leucophaeum_ Fr., Rost., _Mon._, p. 113, Figs. 77, 78.
1899. _Physarum leucophaeum_ Fr., Macbr., _N. A. S._, p. 21.
1911. _Physarum nutans_ Pers., sub-species _leucophaeum_ (Fr.) Lister,
_Mycet., 2nd ed._, p. 67.
Sporangia scattered or gregarious, stipitate; the peridium globose or
sub-depressed, plano-convex, but never umbilicate below, erect,
bluish-ashen; the stipe short, rugose, sub-sulcate, fuscous, brown, or
sometimes almost white, even or slightly attenuate upward from a
thickened base or sometimes from an indistinct hypothallus; capillitium
dense, intricate; the nodules white, with comparatively little lime,
thin, expanded, angular or branching; columella none; spore-mass black,
spores violaceous, minutely roughened, about 8-10 mu.
This extremely delicate and beautiful form is certainly not to be
referred to _Tilmadoche alba_ (Bull.) Fr. Fries, who seems to have known
of _P. compressum_ A. & S. and refers _it_ to _P. nutans_ Pers., _op.
cit._, p. 130, annotates the present species: "Species especially
remarkable in the stipe, in the internal structure, and in its whole
habit, nor is there any other with which it may be compared. Peridium
thin, not uniform, presently breaking up into laciniate scales; at first
yellow, then bluish-ashen; when empty, white. The form inconstant,
globose, depressed, but never umbilicate at the base." If we may judge
by what Fries says on the subject, he certainly distinguished clearly
between this species and _T. alba_ (Bull.), to say nothing of the
stouter, larger, in every way coarser forms called by Rostafinski _P.
nefroideum_, _P. compressum_, _P. lividum_, etc.
The shadowy little species has had an eventful history, dipping in and
out of our story in most uncertain fashion. Beginning with Fries, as
noted, it received confirmation at the hands of DeBary, and by
Rostafinski was given priority over a long list of synonyms, and
figured. The earlier English authors follow Rostafinski, but for Lister
in the _Mycetozoa_, p. 51, the species becomes a synonym of _T. alba_ as
_P. nutans_, the description appropriately enlarged to receive it.
Meantime American students generally confused it with the tilmadoches on
the one hand and _P. nefroideum_ R. (supposed) on the other. In 1897,
Robt. Fries in _Sver. Myxom. Flora_, brings the species again to view as
co-partner with _P. nutans_ and in the _Mycetozoa, 2nd ed._, p. 67, it
appears as sub-species to the same.
The resemblance to _P. album_ or _P. nutans_, is chiefly as intimated, a
matter of definition; real differences are found in the irregular
capillitium, fitting a globose sporange, in the character of the stipe
and the consequent pose. See under _P. nutans_ and _P. notabile_.
34. PHYSARUM NODULOSUM _Cke. & Balf._
1881. _Physarum nodulosum_ Cke. & Balf., _Rav. N. A. F._, Exsic., 479.
1889. _Badhamia nodulosa_ Massee, _Jour. Myc._, Vol. V., p. 186.
1891. _Physarum calidris_ Lister, _Jour. Bot._, Vol. XXIX., p. 258.
1896. _Craterium nodulosum_ (Cke. & Balf.) Morg., _Jour. Cin. Soc._,
p. 87.
1899. _Physarum nodulosum_ Cke. & Balf., Macbr., _N. A. S._, p. 51.
1911. _Physarum pusillum_ List., _Mycetozoa, 2nd ed._, p. 64.
Sporangia gregarious; minute, globose, bluish-white, the sporangial wall
thin and more or less encrusted with lime, breaking up irregularly,
stipitate; stipe slender, longer than the sporangium, attenuate upward
or even, bright brown, rugose, expanded above into a shallow cup-like
base for the sporangium; columella none; capillitium with lime-knots
more or less abundant, white, often uniting, badhamioid; spore-mass
black; spores by transmitted light, pale lilac-brown, almost smooth,
10-12 mu.
Pennsylvania, Ohio, Iowa; Canada.
One of the smallest species of the genus, by its proportionally long
stipe and small round sporangium reminding one somewhat of _P.
globuliferum_; much smaller, however, and in every way different. The
generic characters are mixed, and the species has been accordingly
variously referred. The lower part of the peridium is sometimes
persistent after the dehiscence, and so far reminds of _Craterium_. But
this character is not constant, and even at best the persisting part is
very small, not greater than in _P. melleum_, for example. On the other
hand, the capillitium in some sporangia is strongly calcareous, reminds
of _Badhamia_, but in most sporangia the _Physarum_ characters are
sufficiently clear.
In the Kew Herbarium, it is said, are two American specimens under one
label, "_Didymium pusillum_." One specimen is a didymium indeed, but, as
it appears, _D. proximum_ Berk., already described. The other is a
physarum. It is proposed in _Mycetozoa, 2nd ed._, to use the combination
thus set free, as if applied by the original author to the second
specimen, _not_ didymium, and to make the new combination date from 1873
and so take precedence of the binomial applied in 1881 by Cooke and
Balfour here retained by the law of priority.
35. PHYSARUM MACULATUM _Macbr._
PLATE XIV., Figs. 6, 6 _a_, 6 _b_.
1893. _Bull. Lab. Nat. Hist. Iowa_, II., p. 383.
1899. _Physarum maculatum_ Macbr., _N. A. S._, p. 47.
1911. _Physarum tenerum_ Rex., Lister, _Mycetozoa_, p. 52, in part.
Sporangia scattered or gregarious, very small, .3-.4 mm., dull gray,
thin-walled, dotted with minute, white calcareous granules, stipitate;
stipe long, about 2 mm., stout, attenuated upward, striate
longitudinally or wrinkled, filled with irregular yellow masses of lime
and accordingly bright yellow in color; columella none; capillitium
forming a dense net, with comparatively small yellow nodular
thickenings; spores globose, purplish, each minutely papillose and
displaying several scattered spots occasioned by local development of
the papillae; diameter of the spores 9-10 mu.
This species was set up for the reception of certain material collected
by Professor Shimek, in 1892, in Nicaragua. It remains so far unique.
The small globose sporangium mounted upon a long upwardly tapering
stipe, .5 mm. thick below, but narrowed at the extreme base where it is
lightly attached, a stem which is simply a sack stuffed with yellow
lime-granules;--this and the yellow capillitium are distinguishing
features. The capillitium and spores suggest _Tilmadoche viride_, but
the entire habit precludes such reference. Perhaps nearest to _P.
melleum_.
Castillo, Nicaragua.
Miss Lister thinks this the same as _P. tenerum_ Rex. But the whole
habit and external appearance are different; the stipe notably long,
clumsy, surcharged with lime; a very singular form.
36. PHYSARUM DIDERMOIDES (_Pers._) _Rost._
PLATE IX., Figs. 1, 1 _a_, 1 _b_, 1 _c_.
1801. _Spumaria (?) didermoides_ Acharius, Pers., _Syn. Fung._,
p. xxix.
1829. _Diderma oblongum_ Fr., _Syst. Myc._, III., p. 103.
1831. _Spumaria licheniformis_ Schw., _N. A. F._, p. 261, No. 2364.
1832. _Physarum atrum_ Schw., _Syn. Fung., Am. Bor._, p. 258.
1875. _Physarum lividum_, Schw., Rostafinski, _Mon._, p. 96.
1875. _Physarum didermoides_ (Ach.) Rost., _Mon._, p. 97.
Plasmodium pale, watery-white or gray; sporangia crowded, ovoid or
cylindric, stipitate or sessile, blue-gray, often capped with white;
stipe variable in length and structure, where well developed pure white,
often flattened, expanded and diaphanous, connate with others through
the irregular reticulate or sheet-like hypothallus; columella none;
capillitium ample, the lime knots angular or rounded, white connected by
hyaline threads; spores in mass black, by transmitted light dark violet,
decidedly spinulose, 12-15 mu.
A very variable species in many particulars. The sporangia in the same
cluster are stipitate and sessile, ovoid and spherical. Our description
does not quite agree with that of Rostafinski. As may be seen from the
plate, it is the _outer_ peridium that is with us white, burdened with
lime, the inner is simpler and comparatively thin. The whiteness of the
outer peridium is however, easily displaced. The colony may not show it
at all, in which case the peridia remaining give to the fructification
entire a pale lead color, very characteristic. The disposition of the
lime in the capillitium is also notably variable. Specimens occur which
in so far realize Rostafinski's _Crateriachea_; that is, the lime is
massed as a snow-white pseudo-columella in the centre of each
sporangium. In such cases the lime of the outer peridium is scant or
limited in amount, never forming the calcareous cap shown in Fig. 1. The
size of the spores is also variable. Rostafinski gives 12.5-14.2 mu; not
infrequently a single spore reaches 16 mu, a very unusual range of
variation.
The species is not common in the upper Mississippi valley, but can be
obtained in quantity where once it appears, as the plasmodia are
profuse.
Ohio, Carolinas, Tennessee, Iowa, South Dakota, Kansas. Especially to be
looked for on the bark of fallen stems of _Populus_ and _Negundo_.
Brazil, India, Japan.
_Physarum lividum_ Rost., _Mon._, p. 95, is but a less calcareous form
of this, as is evident even by the author's description. Professor
Morgan thought _P. lividum_ a phase of _P. griseum_ Lk. Link, however,
reckons _P. griseum_ the same as _P. cinereum_. Link, _Diss._, I., p.
27.
37. PHYSARUM LEUCOPUS _Link._
PLATE IX., Figs. 7, 7 _a_, 7 _b_.
1809. _Physarum leucopus_ Link, _Diss._, I, p. 27.
Sporangia gregarious, stipitate, globose snow-white, with a didymium
like covering of calcareous particles; stipe white, not long, conical or
tapering rapidly upward, slightly sulcate, brittle, from an evanescent
hypothallus; columella none or small; capillitium, consisting of rather
long hyaline threads, connecting the usual calcareous nodes, which are
large, angular, snow-white; spore-mass black; spores by transmitted
light, violet-brown, distinctly warted, about 10 mu.
The snow-white, nearly smooth stem, the small sporangium (1/2 mm.)
covered with loose calcareous granules, distinguish this rare species.
It looks like a small _Didymium squamulosum_. Fries called it _D.
leucopus_, _Syst. Myc._, III., p. 121.
Rare. Iowa, Ohio, Maine; Portugal.
38. PHYSARUM COMPRESSUM _Alb. & Schw._
PLATE XVIII., Fig. 14, and PLATE XIX., Fig. 12 and Fig. 4.
1805. _Physarum compressum_ Alb. & Schw., _Fung. Lus._, p. 97.
1875. _Physarum nefroideum_ Rost., _Mon._, p. 93, in part.
1875. _Physarum affine_ Rost., _Mon._, p. 94.
1909. _Physarum compressum_ Alb. & Schw., Torrend, _Fl. des Myx._,
p. 197.
1911. _Physarum compressum_ List., _Mycetozoa, 2nd ed._, p. 70.
Sporangia more or less scattered, _compressed_-globose, or
compressed-reniform, i. e. often umbilicate, stipitate, sessile, or
elongate as if plasmodiocarpous, calcareous, white or ashen; peridium
thin, covered with squamules, opening irregularly, usually by apical
cleft; stipe, when present, short, stout, more or less sulcate, dark
brown or ashen; capillitium a rather loose net, the nodules white,
variable in size and shape; spores purplish-brown, delicately roughened,
about 10-12.5 mu.
_P. affine_ R. was in this connection set up for European types
compressed indeed, but more strongly _reniform_. The author says in his
further description that the form _affine_ is less definitely
umbilicate, has white stems, etc.; allantoid, one would now say. Such
forms now begin to appear in America; and if for these a specific name
is needed, it is provided, _P. affine_ Rost., Plate XIX., Fig. 4.
This seems to be a cosmopolitan species, now that we have found it.
However, in North America it is rare. It is reported from Pennsylvania,
from Colorado; Harkness found it in California, and the writer has often
collected it in Oregon, on Mt. Rainier, Washington, and in California.
Europe.
39. PHYSARUM NOTABILE _nom. nov._
PLATE IX., Figs. 2, 2 _a_, 2 _b_; PLATE XV., Fig. 2; and Frontispiece.
1873. _Didymium connatum_ Peck, _Rep. N. Y. Mus._, XXVI., p. 74.
1879. _Physarum polymorphum_ (Mont.) Rost., Peck, _Rep. N. Y. Mus._,
XXXI., p. 55.
1893. _Physarum leucophaeum_ Fr., Ellis, _N. A. F._, No. 2396,
_second exhibit_.
1893. _Physarum leucophaeum_ Fries, Macbr., _Bull. Lab. Nat. Hist.
Iowa_, II., p. 156.
1894. _Physarum compressum_ Alb. & Schw., List., _Mycetozoa_, p. 53,
in part.
1896. _Physarum connexum_ Link., Morg., _Jour. Cin. Soc._, p. 92,
in part.
1896. _Physarum confluens_ Pers., Morg., _l. c._, p. 94.
1899. _Physarum nefroideum_ Rost., Macbr., _N. A. S._, p. 41, in part.
1911. _Physarum connatum_ Lister, _Mycetozoa, 2nd ed._, p. 71.
Sporangia gregarious, sessile, stipitate, or even plasmodiocarpous; when
stipitate, depressed, varying at times to irregular reniform in the same
colony; globose, the peridium strongly calcareous, cinereous-white;
stipe variable, generally tapering upward, always distinctly deeply
plicate-furrowed throughout, in color dark, opaque, sometimes touched
with white or gray; capillitium abundant, the white lime-knots, varying
in size and shape, connected by rather long hyaline threads, with here
and there an empty node; spore-mass black, by transmitted light, dark,
sooty brown, minutely papillose, 10-11.5 mu.
This remarkable species, while not at all difficult of recognition to
one familiar with its phases, is withal very difficult to define.
Normally stipitate, it often shows from the same plasmodium all sorts of
forms, the shape of the fructification dependent apparently upon
external conditions prevalent at the time. The amount of calcium also
varies, especially in the capillitium, where there is usually much, with
a tendency to the formation of something like a pseudo-columella; the
outer net in such cases nearly destitute. The calcium in the stipe also
varies; the black or brown stipes are, of course, free from it; the gray
or white, calcareous.
In this large and difficult genus, since spore-color is receiving
increased consideration,--see No. 31 preceding,--it is proper to note
that in the present case two types appear, one with spore-color under
the lens, as described, the other with spores violaceous with no trace
of black; unshadowed.
The preceding description is based on material assembled during forty
years. The form is easily discoverable by any collector throughout the
entire valley of the Mississippi and eastward to Nova Scotia. For its
naming, students in America have vainly waited the decision of those
having access to mycologic types in Europe. It seems now certain that
the species is extremely rare in the old world if there occurrent; never
seen by any of the earlier taxonomists including Fries and Rostafinski;
perhaps adventitious in these later years, although thus far no specimen
from Europe has reached this table.[24] _P. nefroideum_ of Strasburg
herbarium turns out, after all, _teste_ Lister, to be _P. compressum_
Alb. & Schw., which accordingly shall now enjoy state and station of
its own; our concern in European nomenclature, in the present instance,
almost disappears, and we return to our synonymy from this side of the
sea.
Mr. Lister would recur to Dr. Peck's _Didymium connatum_, which indeed
represents the present species. In such disposition, how gladly would
all concur, were the thing possible! But _Physarum connatum_ is already
a synonym twice over.[25] Unless we are done with the rules entirely,
_P. connatum_ cannot stand. _P. polymorphum_ and _P. leucophaeum_ are
names already in use, of course; and so under the circumstances, much as
it is to be regretted, there would seem nothing left to do but to cancel
all past synonymy and impose a new name whose permanence may at least be
hoped for, if not expected.
40. PHYSARUM TROPICALE _Macbr._
1899. _Physarum tropicale_ Macbr., _N. A. S._, p. 45.
PLATE XV., Figs. 4, 4 _a_, 4 _b_.
Sporangia scattered, gregarious, turbinate, short stipitate, blue-gray,
about 1 mm. in diameter; peridium above iridescent, green, blue, etc.,
dotted with minute flecks of white, below limeless, purple or bronze
shading to the brown of the stipe; stipe short, stout, slightly rugose,
cylindric, non-calcareous, brown; columella none; hypothallus none;
capillitium abundant, the nodes generally calcareous, small, uniform,
angular, white, uniformly distributed; spore-mass, black; spores dark
violet-brown, distinctly and closely warted, 12-15 mu.
A large handsome species recognizable by the peculiar turbinate
sporangium, with its iridescent peridial wall in which green strongly
predominates above, bronze below. The distinction between the upper and
lower peridium would suggest _Craterium_, but the internal structure is
not at all _Craterium_-like. The capillitium is typically of _Physarum_.
The color suggests _P. leucophaeum violascens_ Rost. From this species
it is at once distinguished by its much longer sporangia, larger and
rougher spores.
Mexico; _C. L. Smith_: Sure to be again collected once that unhappy
country shall again open its forests to research.
41. PHYSARUM NICARAGUENSE _Macbr._
PLATE XV., Figs. 7, 7 _a_, 7 _b_; XVII., 11 and 11 _a_.
1893. _Physarum nicaraguense_ Macbr., _Bull. Lab. Nat. Hist. Iowa_,
II., p. 383.
1894. _Physarum compressum_ Alb. & Schw., List., _Mycetozoa_, p. 53,
in part.
1910. _Physarum nicaraguense_ Macbr., Petch, _Mycetozoa Ceylon_,
p. 334.
1911. _Physarum reniforme_ List., _Mycetozoa, 2nd ed._, p. 72,
in part.
Sporangia multilobate or compound-contorted, below obconic, gray, ribbed
with calcareous thickenings; stem short, fuscous, longitudinally
wrinkled; hypothallus distinct, black; columella none, although the lime
massed at the centre of each sporangium simulates one; capillitium
white, densely calcareous, with heavy angular nodules connected with
comparatively short threads; spores violet, globose, spinulose, about 12
mu in diameter.
Ometepe, Nicaragua. _Professor B. Shimek_.
This species resembles in some particulars No. 39, especially in the
amount of lime present in both capillitium and peridium, in the fluted,
sooty stipe, and the rough spores. Mr. Lister once regarded it as the
same. Nevertheless, it differs from _P. notabile_ in many definite
particulars. In the first place, the sporangia are different in form and
habit. They are obconic, nearly always compound, convolute, or botryoid,
in this respect somewhat resembling _P. polycephalum_. Besides, the
sporangia are uniformly much smaller, and show constantly the strongly
calcified centre, much transcending anything seen in _P. notabile_. The
stipe also is peculiar, quite short, an upward extension or sweep of the
common hypothallus which is usually very distinct or prominent; and,
while the stipe is longitudinally wrinkled, it is much less so than in
the related species, and in a different way. The spores are about the
same in size, but differ in color, in this respect agreeing rather with
_P. leucophaeum_.
In the _Mycetozoa, 2nd ed., l. c._, the present species is entered as a
synonym of two described by Massee: _Tilmadoche reniformis_ Mass., Mon.,
p. 336, and _Didymium echinosporum_ Mass., _Mon._ 239. But Massee's
description of his tilmadoche is, naturally enough, at variance in every
important point with the facts in the species before us. Massee says:
"... sporangia deeply umbilicate _below_, sausage-shaped and curved; the
stem elongated slender erect, pale brown; capillitial nodes scattered,
fusiform, colorless or yellow; spores 16-17 mu." It is evident that
whatever Massee may have had in hand as he wrote it was _not P.
nicaraguense_, which has spores 10-12 mu and reverses the remaining
description.
But _Didymium echinosporum_ also defines _T. reniformis_ since Lister,
_Mon._, p. 54, says they are based on two gatherings of one species. Of
this second species Massee says: "A superficial resemblance to _T.
nutans_, but distinct in the capillitium which contains _no trace of
lime_; spores 12-14 mu!" Again it is evident that whatever Massee had in
hand when he wrote, it was not _P. nicaraguense_ which "has capillitium
almost Badhamia-like," i. e., burdened with lime!
Worse than all; Mr. Massee's _alleged_ types are in evidence; one
labelled _P. reniforme_[26] includes forms of _P. didermoides_ and of
_P. nicaraguense_; the other labelled by Berkeley _P. nutans_ is _P.
nicaraguense_. So Mr. T. Petch, _Mycet. Ceyl._, who enters our species
as from Ceylon, and the names cited from Berkeley, Massee, and others,
as synonyms. He remarks, "Probably Thwaites' 135 and 55 were mixed
during examination"! Doubtless! and some other things too! What Massee
did have beneath his lens, no one now may say but apparently not in
either case cited, the physarum of Central America.
42. PHYSARUM SULPHUREUM _Alb. & Schw._
1805. _Physarum sulphureum_ Alb. & Schw., _Consp. Fung._, p. 93,
Tab. VI, f. 1.
1818. _Physarum flavum_ Fries, _Symb. Gast._, p. 22.
1875. _Physarum sulphureum_ Alb. & Schw., Rost., _Mon._, p. 101.[27]
Sporangia gregarious, sub-globose, rugulose-squamulose, .6-.8 mm.,
sulphur-yellow, stipitate; peridium membranous, covered with calcareous
scales; stipe stout, white, charged with lime, furrowed; columella none;
capillitium strongly calcareous, the nodules large, white; spores
violaceous, rough, 9-11 mu.
Northern Europe. (Lusatia) Lausitz, Alb. & Schw.; dim old Wendish
region on the south borders of Brandenburg. Reported also from Sweden.
The description and figure given by Schweinitz, 1805, _l. c._, leave no
doubt as to what he had in hand. Twenty or thirty years later, having
spent the interval in this country,--bishop, indeed, of the Moravian
churches, but a student of fungi all the while,--he reports the same
thing from this country; _Proc. Phil. Acad. Sci._, 1834. Cooke also
lists it in _Myxomycetes of the U. S._ It surely will be found again.
Mr. Lister thinks _P. variable_ Rex may be the same thing.
43. PHYSARUM CARNEUM _G. Lister and Sturgis_.
1910. _Physarum carneum_ G. Lister and Sturgis, _Jour. Bot._,
Vol. XLVIII, p. 63.
Sporangia gregarious, stipitate, sub-globose, .5 mm. in diameter,
ochraceous-yellow above, flesh-colored below; peridium membranous, pale
yellow, lime-granules evenly distributed; stipe short, translucent,
pinkish flesh-colored; capillitium dense, nodules white; spores
purplish-brown, spinulose, 8 mu.
Differs from _P. citrinellum_ in the membranous peridium, flesh-colored
stalks and smaller spores.
Colorado; _Dr. W. C. Sturgis._
44. PHYSARUM CITRINELLUM _Peck._
1831. _Physarum caespitosum_ Schw., Syn. _N. A. F._, No. 2301 (?).
1869. _Diderma citrinum_ Peck, _Rep. N. Y. Mus._, XXII., p. 89.
1870. _Physarum citrinellum_ Peck, _Rep. N. Y. Mus._, XXXI., p. 55.
1894. _Craterium citrinellum_ List., _Mycetozoa_, p. 74.
1899. _Physarum caespitosum_ Schw., Macbr., _N. A. S._, p. 37.
1911. _Physarum citrinellum_ Peck, List., _Mycetozoa, 2nd ed._, p. 62.
Sporangia gregarious, or scattered globose, short-stipitate, pale yellow
or ochraceous, smooth or slightly roughened by the presence of minute
lime-particles; peridium more or less distinctly double, the outer
calcareous, fragile, the inner very delicate, with here and there a
calcareous thickening, ruptured irregularly; stipe very short, half the
sporangium, fuliginous, furrowed, expanded below into an imperfectly
defined hypothallus; capillitium abundant, the nodes stellate-angular,
large, the internodes delicate, short; spore-mass black, spores
violaceous-brown by transmitted light, strongly spinulose, 10-12.5 mu.
A very distinct and handsome species. Easily recognizable at sight by
its large, globose, almost sessile and yet distinctly stalked sporangia.
The color to the naked eye is pale ochraceous or buff. Only under a
moderate magnification do the citrine tints come out.
In the _Twenty-second N. Y. Report_, Dr. Peck incorrectly referred this
species to _Physarum citrinum_ Schum. On the appearance of Rostafinski's
_Monograph_, Dr. Peck in his revised list, _l. c._, writes _P.
citrinellum_ Peck, with description on p. 57, following. Under the last
name the species has been generally recognized in the United States and
distributed. _N. A. F._, 2490.
In the former edition, this species was referred to _P. caespitosum_
Schw., of which the original description is as follows: "_P.
caespitosum_ L. v. S., pulcherrimum. In foliis et stipitibus
Rhododendri, Bethlehem. Physarum substipitatum aut saltem basi
attenuata, caespitosim crescens et sparsim. Caespitulis 3 linearibus;
peridiis stipatis, turbinatis, ovatis, basi contracta membranula
exterori luteosquamulosa aut punctato-squarrulosa. Sporidiis
nigro-brunneis, floccis citrinis inspersis." _Synopsis N. A. Fungi_,
2301.
The type from the Schweinitz herbarium is no longer in evidence. Without
it, the reference cannot be sustained.
Not uncommon in the eastern United States; reported also from Japan.
45. PHYSARUM ALBESCENS _Ellis._
PLATE XVI., Figs. 4, 4 _a_.
1889. _Physarum albescens_ Ellis _in litt_: not described.
1893. _Physarum auriscalpium_ Cke., Macbr., _Bull. Lab. N. H. Iowa_,
No. 2, p. 155, in part.
1894. _Physarum virescens_ var. _nitens_ List., _Mycetozoa_, p. 59,
in part.
1899. _Physarum virescens_ var. _nitens_ List., Macbr., _N. A. S._,
p. 34, in part.
1899. _Leocarpus fulvus_ Macbr., _N. A. S._, p. 82.
1911. _Physarum fulvum_ Lister, _Mycet., 2nd ed._, p. 60.
1911. _Physarum virescens, nitens_ List., _Mycet., 2nd ed._, p. 84,
in part.
Sporangia gregarious, scattered, ovoid or globose, pale yellowish or
fulvous, opening irregularly above, stipitate; the peridium double, the
outer layer more or less calcareous, the inner delicate, almost
indistinguishable, persistent below as a shallow cup; the stipe long,
weak, striate, fulvous or yellow; hypothallus distinct, venulose, or
more or less continuous; capillitium pallid or white, dense, with here
and there below large continuous yellow calcareous nodules; columella
none; spore-mass black; spores by transmitted light, dark brown, rough,
13-15 mu. Varies to forms with single (inner) peridium and simple
physaroid capillitium. _Vid._ descriptions cited for _P. auriscalpium_,
_P. nitens_, etc.
This interesting form is from our western mountains, and suggests at
first a diderma; but the capillitium is entirely unlike that of a
diderma in color and structure, and plainly belongs here. Plasmodium
yellow, on fallen leaves and twigs. Our material is from Prof. Bethel,
Denver; and Lake Tahoe, Nevada; later from Dr. Weir, Montana. No doubt
common at high altitudes near the snow-line in mountainous regions,
probably around the world.
As indicated above, this was originally entered as of the genus
_Leocarpus_; the taxonomic history of the form may interest readers who
note with surprise the presentation in synonymy here developed.
About thirty-five or forty years ago Dr. Harkness of California sent to
Mr. Ellis of New Jersey a slime-mould which the sender referred to
_Diderma albescens_ Phillips, (_Grev._ V., p. 114, 1877). Ellis sent a
small bit to the Iowa herbarium without other comment, save that he
thought it a physarum. Sometime later Mr. Ellis received from Father
Langlois, a correspondent in Louisiana, specimens he esteemed the same
thing. He expressed the opinion that if this were what Phillips had
found in California, it should perhaps be called a physarum. The
Louisiana material by his courtesy came also to this table. The material
was scanty, in poor condition, and all waited further light. To these
specimens the writer paid less attention. They were in the hands of his
correspondents and the courtesy of the case required their further
consideration by Dr. Rex.
In 1889 Mr. Holway found in Iowa, a physarum of which he sent part to
Ellis and the remainder to the writer who, then engaged on the
_Myxomycetes of East. Iowa_, referred his part of this Iowa gathering
to the _Physarum auriscalpium_ Cke. as found in New York. Under this
caption a specimen was later sent to Mr. Lister, who has, as we see,
consistently regarded the thing as a variety of _P. virescens_ Ditmar,
_P. nitens_ List.
Meantime in 1898 Colorado material from Professor Bethel reached the
University. This did not recall any of the materials sent from Ellis.
_Diderma albescens_ had meanwhile come again from California, and been
recognized as _Diderma niveum_ Rost.
Accordingly, in _N. A. S._ the latest arrival from Colorado was
described as a new species, and with some temerity perhaps, offered as a
second species of the hitherto monotypic _Leocarpus_, all on account of
the peculiar capillitium. Sometime after publication our most valued
correspondent Mr. Bilgram called attention to the resemblance between
the Colorado and Louisiana material already referred to. The University
specimens as stated were small, broken, and in every way poor, but
enough remained to indicate the evident justice of our correspondent's
suspicion. Further investigation of the Holway material in Philadelphia
showed that _it too was entitled to consideration_! Inasmuch as the
Holway sending was all from one plasmodium, all difficulties vanished at
once. The Iowa gathering showed two phases: one at the University
represents _P. nitens_, physaroid, single-walled; while the Philadelphia
part of the gathering corresponds, poorly it is true, but in fact, as
_now_ appears, to the form coming in perfection from Colorado;
leocarpine in structure, published as _Leocarpus fulvus_; _P. fulvum_
Lister. Since the combination _P. fulvum_ is already in use, synonym of
_P. rubiginosum_, it seems better to write the name suggested by Ellis;
_Physarum albescens_ never having been published, because _Diderma
albescens_, as noted took care of itself.
Since Rostafinski we separate all these physaroid forms chiefly by
capillitial characters: capillitial structure separates genera.
_Physarum diderma_ is a physarum despite its double wall. And so here
_Leocarpus_ was set out by its differentiating capillitium. In good
specimens of the present species a large part of the capillitial net is
entirely free from lime, so that when the peridium first opens at the
summit, sometimes no trace of lime appears; the calcareous deposits are
below, and tend to occupy not the nodal intersections as in _Physarum_,
but in large masses involve portions of the net itself, nodes and all,
as in _Leocarpus_. Miss Lister's beautiful figures, _op. cit._, Figs. 66
and 82, show this very well.
In The _Journal of Botany_, 52, p. 100, the distinguished author and
artist records the discovery of this species in the mountains of
Switzerland. She says: "This specimen shows a striking resemblance to
_Leocarpus fragilis_ Rost., both in the shape of the sporangia and in
the capillitium and spores; but although the color of the sporangia
varies in both these species, the walls of _P. (L.) fulvum_ are
membranous and rugose with included deposits of lime granules and show
nothing of the polished cartilaginous layers characteristic of _L.
fragilis_."
The species is a boundary type at best, and shows again how artificial
all our taxonomy is apt to prove, when the number of presentations of
some particular type becomes larger.
For these reasons, the present author writes _Physarum_, and believes
the question of identity in a perplexing case fortunately settled.
46. PHYSARUM VARIABILE Rex.
1893. _Physarum variabile_ Rex, _Proc. Phil. Acad._, p. 371.
1911. _Physarum variabile_ Rex, List., _Mycetozoa, 2nd ed._, p. 47.
Sporangia scattered, stipitate, sub-stipitate or sessile, about 1 mm.
high; regularly or irregularly globose, ellipsoidal, obovate or
cylindric-clavate in shape; sporangium wall sometimes apparently thick,
of a dingy yellow or brownish-ochre color, slightly rugulose on the
surface, crustaceous, brittle, rupturing irregularly, sometimes thin,
translucent, covered externally with flat circular calcic-masses falling
away in patches; stipes nearly equal, occasionally much expanded at the
base, rough, longitudinally rugose, variable in size, sometimes
one-third of a millimetre high, sometimes a mere plasmodic thickening of
the base of the sporangium; color of stipes varying from a
yellowish-white to a dull brownish-gray; capillitium a small-meshed
network of delicate colorless tubules with large, many-angled, rounded
masses of white, or rarely yellowish-white lime-granules at the nodes;
no true columella, but often a central irregular mass of white
lime-granules; spores dark violet-brown, verruculose, 9-10 mu.
Pennsylvania. _Dr. Rex._
Lister, _op. cit._, describes a variety, _sessile_, presenting
plasmodiocarpous fructification, from Ceylon, also from Antigua, but
there are some doubts as to the identity of these with American sessile
and plasmodiocarpous forms. Vid. _Jour. Bot._ XXXVI., p. 113.
47. PHYSARUM AURISCALPIUM _Cooke_.
1877. _Physarum auriscalpium_ Cooke, _Myx. U. S._, Am. Lyc. Nat. Hist.
N. Y., XI., p. 384.
1877. _Physarum auriscalpium_ Cke., _Myx. Gr. Brit._, Pl. 24,
f. 253-4.
1893. _Physarum sulphureum_ (Alb. & Schw.), Sturgis, _Bot. Gaz._,
XVIII., p. 197.
1898. _Physarum auriscalpium_ Cke., List., _Jour. Bot._, XXXVI.,
p. 115.
1911. _Physarum auriscalpium_ Cke., List., _Mycetozoa, 2nd ed._,
Syn. excl.
Sporangia scattered, stipitate or occasionally sub-sessile spherical,
.8-1 mm. high; peridium granulated, bright golden yellow; stipe, when
present, one-half to two-thirds the height of the sporangium,
blackish-brown; hypothallus, minute, thin, brown; columella absent;
capillitium rather dense, composed of large angular nodes, completely
filled with bright yellow granules of lime, and connected by very short,
delicate, colorless internodes destitute of lime; spores globose
minutely verruculose, or asperate, 10.7-11.8 mu in diameter,
brownish-violet by transmitted light, black in the mass.
This is the original description, 1893, of _P. sulphureum_ (Alb. &
Schw.) Sturgis; the author last named having compared certain stalked
New England forms with what he could find of _P. sulphureum_ in the
herbarium of Schweinitz at Philadelphia, and having, as he thought,
established identity.
Meantime Mr. Lister had been inclined to refer _P. auriscalpium_ Cke. to
_P. rubiginosum_ Fr., _Mycetozoa_, p. 61.
In 1898 Professor Sturgis and Mr. Lister agreed that the New England
specimens, owing to color and character of stipe and some other
differences could not be the Schweinitzian species, but did indeed
conform much better with those in London labelled _P. auriscalpium_ Cke.
Accordingly _P. sulphureum_ is something else, very different, (v. A. &
S., Cons. _Fung. Tab._, VI., f. 1), and by aid of recent[28] discoveries
in Sweden goes its own way again. Meanwhile _P. sulphureum_ Sturgis
stands, a new type for _P. auriscalpium_ Cke., the description modified
to suit; the lamented pioneer-author receives honor due, and his
handsome species, with its "golden graving," may now march, let us hope,
under appropriate banner far down the fair highway to future fame!
48. PHYSARUM OBLATUM _Macbr._
PLATE III., Fig. 6; PLATE XIV., Figs. 3, 3 _a_, 3 _b_.
1879. _Physarum ornatum_ Peck, Rep. _N. Y. Museum_, XXXI., p. 40 (?).
1893. _Physarum oblatum_ Macbr., _Bull. Lab. Nat. Hist. Iowa_, II.,
p. 384.
1896. _Craterium maydis_ Morg., _Myx. Miam. Vall._, p. 87.
1909. _Physarum maydis_ Torr., _Flor. des Myxo._, p. 193.
1911. _Physarum maydis_ Torr. List., _Mycet., 2nd ed._, p. 59.
Sporangia gregarious, stipitate, small, bright yellow, globose or
depressed-globose, rough; stipe reddish-brown or fuliginous, even,
short, slender; hypothallus scant, black, or none; columella none;
threads of the capillitium yellow, delicate, connecting the rather dense
and abundant yellow lime-granules; spore-mass brownish-black, spores
violaceous, minutely but distinctly spinulose, 9-11 mu.
This species is easily recognizable by its brilliant yellow color,
somewhat rugose, sometimes scaly peridium, its richly calcareous
capillitium, also bright yellow where not weathered or faded, its dark
brown, translucent, non-calcareous stem. In dehiscence, the base of the
peridium in cup-form, sometimes persists. This circumstance, with the
fact that decaying maize-stalks and leaves are a favorite habitat, led
Professor Morgan to its description as _Craterium maydis_. But it is
doubtless a physarum, occurring on habitats of all sorts, from Ohio to
Iowa, Colorado and Washington. Ceylon(?).
_Physarum ornatum_ Peck is doubtfully cited here, although Professor
Morgan thought it the same as _P. oblatum_. As a matter of fact the
original brief description, _op. cit._, does not suggest either _P.
oblatum_ or _P. maydis_; rather a form of _Tilmadoche viridis_.
Professor Sturgis, _Notes on Some Type Specimens of Myxo., in the N. Y.
Museum, Trans. Conn. Acad. Arts and Sci._, Vol. X., Pt. 2, p. 470, says
that of the type almost nothing remains, that the name _P. ornatum_ Pk.
"should be discarded."
49. PHYSARUM GALBEUM _Wing._
1890. _Physarum galbeum_ Wing., Ell., _N. A. F._, 2491
(no description).
1892. _Physarum petersii_ Berk. & C., Mass., _Mon._, p. 296, in part.
1894. _Physarum berkeleyi_ Rost., List., _Mycetozoa_, p. 48, in part.
1899. _Physarum galbeum_ Wing., Macbr., _N. A. S._, p. 53.
1911. _Physarum galbeum_ Wing., List., _Mycetozoa, 2nd ed._, p. 59.
Sporangia scattered, globose, stipitate, often nodding, golden yellow,
the peridium exceedingly thin, breaking up into patches on which the
yellow lime granules are conspicuous; stipe non-calcareous, pale brown
or amber-colored, longitudinally wrinkled, about one and one-half times
the diameter of the peridium; columella none; hypothallus none;
capillitium dense, extremely delicate, the nodes only here and there
calcareous, the lime knots when present small, angular, yellow;
spore-mass pale brown; spores almost smooth, lilac- or violet-tinted,
7.5-10 mu.
Distinguished among the small delicate species with which it will be
naturally associated, by the yellow, richly calcareous wall of the
globose sporangium and the almost limeless capillitium. The stipe is
hollow and contains irregular masses of refuse granular matter, but no
lime so far as we have been able to discover. _P. flavicomum_, to which
the species is related most closely, differs in having the wall
non-calcareous, iridescent, as well as in the color throughout; the
character of the capillitium, in which lime is abundant; the absence of
refuse-matter in the stem.
Pennsylvania, Iowa, Minnesota.
50. PHYSARUM TENERUM _Rex._
1890. _Physarum tenerum_ Rex., _Proc. Phil. Acad._, p. 192.
1894. _Physarum polymorphum_ Rost. var. _obrusseum_, Lister,
_Mycet._, p. 48.
1899. _Physarum obrusseum_ (Berk. & C.) Rost., Macbr., _N. A. S._,
p. 52.
1911. _Physarum tenerum_ Rex., List., _Mycetozoa, 2nd ed._, p. 52.
The peridium thin, membranaceous, thickly studded with circular,
flattened, yellow granules of lime; stipe long, slender, subulate,
opaque, pale brown, striate and black below, pale yellow above;
columella none; capillitium yellow or white, delicate, forming a loosely
but regularly meshed network with numerous small round or rounded
granules at the intersections; spores dark brown, delicately warted, 7-8
mu.
This delicate physarum, very fragile and evanescent, seems to be
distinct, by reason of its characteristic rounded lime granules, from
any similar, stipitate species. It varies a little according to
locality. Ohio specimens are a little larger and have thicker and more
calcareous stipes than is usual in those from Philadelphia. The walls of
the sporangia when fully matured generally break into several petal-like
segments which finally become reflexed. The description given by
Berkeley is entirely insufficient.
In an earlier edition this species was entered as _P. obrusseum_
following the Polish text. Miss Lister who has the type of _Didymium
obrusseum_ at hand considers it as representing a phase of _Physarum
polycephalum_ Schw. _D. tenerrimum_ Berk. & Curt. is judged the same.
_P. tenerum_ Rex is, in any event, certain, and the combination is
adopted.
Rare:--Pennsylvania, Ohio, Louisiana, Texas, Iowa, Portugal, Japan.
51. PHYSARUM FLAVICOMUM _Berk._
PLATE XV., Figs. 3, 3 _a_.
1845. _Physarum flavicomum_ Berk., _Hook. Jour. Bot._, IV., p. 66.
1873. _Physarum cupripes_, Berk. & Rav., _Grev._, II., p. 65.
1875. _Physarum berkeleyi_ Rost., _Mon._, p. 105.
1894. _Physarum berkeleyi_ Rost., List., _Mycetozoa_, p. 57.
1899. _Physarum flavicomum_ Berk., Macbr., _N. A. S._, p. 53.
1911. _Physarum flavicomum_ Berk., List., _Mycetozoa, 2nd ed._, p. 58.
Sporangia gregarious, small, spherical, at first fuliginous throughout,
stipitate; the peridium thin, destitute of lime, iridescent, breaking up
and deciduous in patches, except at the base; stipe twice the diameter
of the peridium, brown, fluted, not hollow, tapering upward from a small
but distinct, radiant hypothallus; columella none; capillitium dense,
persistent, the nodes frequently calcareous, elongate and vertical,
especially below, yellow; spore-mass brown; spores by transmitted light,
bright violaceous-brown, slightly papillose, 9-10 mu.
This species is instantly distinguishable from all cognate forms by its
peculiar sooty color. Not less is the species structurally marked by its
capillitium. The latter below is exactly as in the species of
_Tilmadoche_. Indeed, the present species unites characters supposed to
distinguish _Physarum_ from _Tilmadoche_, and would so far justify those
authors who bring all the species of both genera together under one
generic name. In any case the species is by its capillitium entirely
distinct from _P. galbeum_, as well as by the structure of the stipe and
the peridial surface. The plasmodium, at first watery, emerges from
decayed elm logs and soon takes on a peculiar greenish tint preserved
somewhat in the mature fruit.
Rostafinski, _Monograph_, pp. 105, 106, rejects Berkeley's specific
name, _flavicomum_, because it refers to the somewhat indefinite,
characteristic color. As this is no valid reason for change, we have
restored Berkeley's specific name, which by general consent has
priority. _N. A. F._, 3299.
Not common. New Jersey, Ohio, South Carolina, Iowa.
52. PHYSARUM BETHELII (_Macbr._) _Lister_.
1899. _Tilmadoche bethelii_, Macbr., _Exempl. ad Herbaria._
1911. _Physarum gyrosum_ Rost., List., _Mycetozoa, 2nd ed._, p. 75.
Sporangia scattered, globose, umbilicate below, .5-1 mm. in diameter,
iridescent blue, or sometimes tinged by the presence of delicate pale
yellow calcareous scales, stipitate; stipe rather short, black or dark
brown, equal; capillitium dense, radiating from the black, slightly
intrusive summit of the stipe, and from the base of the peridium
ascending; the nodules not numerous, elongate, branching betimes, pale
yellow; spores minutely roughened, 10-12 mu.
This beautiful delicately tinted little species is clearly tilmadochoid
in the Friesian sense. The capillitium persists after the fall of the
upper filmy peridium, adherent below to the persisting peridial base.
Collected thus far twice only; by Professor Bethel and by Professor
Sturgis, Colorado.