The North American Slime-Moulds Part 26

_C. minimum_ Berk. & C. has here priority. Ma.s.see regards this name as indicating a distinct species. We have been unable to determine what the authors really had before them, and adopt accordingly the first available combination.

New England to Iowa and south; reported also from the orient.

5. CRATERIUM CONCINNUM _Rex._

1893. _Craterium concinnum_ Rex, _Proc. Phila. Acad._, p. 370.

Sporangia scattered, usually minute, broadly funnel-shaped, stipitate.

The peridium simple, variously colored by innate lime granules, opening by a regular cap or operculum, brownish white, darkest in the centre, always more or less convex; stipe equalling the cup in height, dark brown, longitudinally ridged; the capillitium a close-meshed network, with small rounded or slightly angular ma.s.ses of ochre-brown lime-granules, larger toward the centre; spores pale brown, minutely warted, 9-10 .

This species differs from the following, to which it seems most nearly allied, in form, color, as in the capillitium, and color of the spores.

In habitat, however, it seems no less distinct, being found always (?) on the spines of decaying chestnut-burs lying on the ground, and in company with that other peculiar species _Lachn.o.bolus globosus_.

The range is probably that of the chestnut, _Castanea dentata_ Borkhausen, east of the Mississippi River.

6. CRATERIUM MINUTUM (_Leers_) _Fr._

PLATE XV., Fig. 5.

1775. _Peziza minuta_ Leers, _Fl. Herborn_, p. 277.

1797. _Craterium pedunculatum_ Trent., Roth., _Catal. Bot._, I., p. 224.

1813. _Craterium vulgare_ Ditmar, Sturm, _Deutsch. Fl. Pilze_, p. 17.

1829. _Craterium pedunculatum_ Trent., Fr., _Syst. Myc._, III., p. 150.

1829. _Craterium minutum_ Leers, Fr., _Syst. Myc._, III., p. 151.

1893. _Craterium pedunculatum_ Trent., Macbr., _Bull. Lab. Nat. Hist.

Iowa_, II, p. 385.

1894. _Craterium pedunculatum_ Trent., Lister, _Mycetozoa_, p. 70.

1899. _Craterium minutum_ (Leers) Fr., Macbr., _N. A. S._, p. 78.

1911. _Craterium minutum_ Fr., List., _Mycetozoa, 2nd ed._, p. 94.

Sporangia scattered, gregarious, cyathiform or turbinate, grayish brown, stipitate, the peridial wall rather thick, double, opening by a distinct lid which lies usually below the slightly thickened and everted margin of the cup; stipe paler, translucent, about equalling in height the peridial cup, longitudinally wrinkled, with hypothallus scant or none; capillitium physaroid, the calcareous nodules large, white, and generally aggregated at the centre of the cup; spore-ma.s.s black, spores by transmitted light violaceous, minutely warted, 8-10 .

This is the most highly differentiated of the whole series. The cup is shapely and well defined, while the lid is not only distinct, but is a thin, delicate membrane of slightly different structure when compared with the peridial wall. It is in all the specimens before us much depressed below the mouth of the sporangium, and the whole structure in our specimens corresponds with Fries' description of _C. pedunculatum_ Trent., while specimens received from Europe correspond to Fries'

account of _C. minutum_ Leers. Nevertheless we are a.s.sured that the two forms are in Europe developed from the same plasmodium, and therefore adopt the earlier specific name as above. _N. A. F._, 2500. This is probably _Fungoides convivalis_ of Batsch and Micheli.

In this species yellow sporangia are sometimes seen. Miss Currie reports from Toronto such variation and in Europe the case seems not unusual.

In fact, there is a yellow tinge about the sporangia of every species listed here, except the first. With the same exception, the plasmodium in every case is yellow.

Common throughout the eastern United States, west to Iowa, Colorado, and south to Louisiana; cosmopolitan.

=5. Physarella= _Peck._

1882. _Physarella_ Peck, _Bull. Torr. Bot. Club_, IX., p. 61.

Sporangium pervious to the base, the interior walls forming a persistent spurious columella; capillitium composed of filaments with here and there minute knot-like thickenings, straight tubes containing lime-granules extending from the exterior to the interior walls of the sporangium, persistently attached to the former.[31]

Such is Dr. Peck's original description of this most peculiar genus. The form of the sporangium in the only species is very variable, but in typical cases is vasiform, the peridial wall at the apex introverted.

The capillitium is like that of _Tilmadoche_, except for the presence of the "straight tubes" emphasized in the original description. These are very remarkable and at once diagnostic. They take origin in the sporangial wall and pa.s.s across to the "columella"; but at the dehiscence of the sporangium, in typical cases, they remain attached at the points of origin, projecting as stout spine-like processes.

PHYSARELLA OBLONGA (_Berk. & C._) _Morg._

PLATE VIII., Figs. 4, 4 _a_, 4 _b_, 4 _c_; PLATE XVI., Figs. 1, 1 _a_, 1 _b_, and 6.

1873. _Trichamphora oblonga_ Berk. & C., _Grev._, II., p. 66.

1876. _Tilmadoche oblonga_ (Berk. & C.) Rost., _Mon. App._, p. 13.

1876. _Tilmadoche hians_ Rost., _Mon. App._, p 14.

1882. _Physarella mirabilis_ Peck, _Bull. Torr. Bot. Club_, IX., p. 61.

1893. _Physarella oblonga_ (Berk. & C.) Morg., _Jour. Cin. Soc._, p. 79.

1894. _Physarella mirabilis_ Peck, List., _Mycet._, p. 68.

1899. _Physarella oblonga_ (Berk. & C.) Morg., Macbr., _N. A. S._, p. 71.

1911. _Physarella oblonga_ Morg., List., _Mycet., 2nd ed._, p. 91.

Sporangia scattered or gregarious, typically cup-shaped or sub-infundibuliform, stipitate, erect or cernuous, but varying through low salver-shaped cups, to irregular applanate and sessile ma.s.ses, the peridium thin but firm, tawny, roughened by numerous yellowish calcareous scales, at length ruptured above and often reflexed in the form of petal-like segments from which project upwards the spiniform trabecules of the capillitium; stipe when present long, terete, red, arising from a scant hypothallus and extended within the sporangium to meet the tubular "columella"; capillitium of delicate violaceous threads seldom branched or united, radiating from the columella with few calcareous nodular expansions, but supported by stout yellow calcareous trabecules, running parallel to the capillitial threads, long adherent to the sporangial wall; spores smooth, globose violet-brown, 7-8 .

Not uncommon in wet places. New York, Ohio, Iowa, South Dakota, Louisiana, Nicaragua; reported also from Ceylon, Java, etc.

Not the least remarkable feature of this remarkable species is the variation in the form of the fruit or sporangia. We have specimens from Louisiana (Rev. Langlois) which show no trace of columella, the whole structure involute and plicate, short stipitate, recalling the extremest complexity of such a species as _P. polycephalum_. _Vid._ Pl. XVI., Fig.

6. Moreover, in these specimens the calcareous deposits are white and not yellow, giving the entire fructification a grayish aspect. Yet there is no doubt we have here simply an exaggerated abnormality of the species; the spores are identical in size, color, and surface.

Plasmodium bright yellow. Dr. Peck gave to his forms the name _Physarella mirabilis_; but specimens sent by Michener of Pennsylvania, and by Berkeley and Curtis described as _Trichamphora oblonga_ (_Grev._, II., p. 66), are the same thing. _N. A. F._, 1212.

_Physarella lusitanica_ Torrend is a globose form depressed above or betimes discoidal, occurring on Eucalyptus trees in Portugal. _P.

oblonga_ is so variable in form that it sometimes suggests a different genus. Forms of it have been mistaken for _Fuligo gyrosa_ R., etc.

Professor Torrend would include here _Physarum javanic.u.m_ (Rac.), i. e.

_Tilmadoche javanica_ as Raciborski saw it! We may not too often reflect that genera are purely artificial things set up for our convenience; but surely _Physarella_ as a natural genus is distinct enough to all.

=6. Cienkowskia= _Rost._

1873. _Cienkowskia_ Rost., _Versuch_, p. 9.

Fructification plasmodiocarpous, irregularly dehiscent, the wall a thin cartilaginous membrane dest.i.tute of lime, except the capillitial attachments within; capillitium scanty but rigid, and characterized everywhere by peculiar hook-like branchlets, free and sharp-pointed, the spores as in _Physarum_, etc.

The genus contains, so far, but a single species:--

CIENKOWSKIA RETICULATA (_Alb. & Schw._) _Rost._

PLATE XIV., Figs. 2, 2 _a_, 2 _b_.

1805. _Physarum reticulatum_ Alb. & Schw., _Cons. Fung._, p. 90.

1829. _Diderma reticulatum_ Fr., _Syst. Myc._, III., p. 112.

1873. _Cienkowskia reticulata_ (Alb. & Schw.) Rost., _Versuch_, p. 9.