calyculus small, plicate-sulcate. Stipe long, erect, brownish-red in
color, expanded at the base into a small hypothallus. Capillitium firmly
attached by numerous threads which are connate with the wall of the
calyculus, much elongated after dehiscence, ovoid-oblong to cylindric,
bright red in color, fading to red-brown or brownish-ochre; the threads
uniform in thickness, about 3 mic., the surface with a series of
prominent half-rings, which wind around the thread in a long spiral.
Spores globose, even, 6-8 mic. in diameter.
Growing on old bark, wood, mosses, etc. The stipe 1-2 mm. in length, the
capillitium elongated 2-4 mm. The commonest of the species, conspicuous
by reason of its bright red color.
2. ARCYRIA MINOR, Schw. Sporangium ovoid-oblong; the calyculus small,
sulcate and ribbed, granulose. Stipe short, erect, brownish-red in
color, standing on a thin hypothallus. Capillitium much elongated after
dehiscence, oblong to cylindric, lax and prostrate, bright red to
brownish in color; the threads uniform in thickness, 2.5-3 mic., the
surface with a series of prominent half-rings, which wind around the
thread in a long spiral. Spores globose, even, 7-9 mic. in diameter. See
Plate I, Fig. 17.
Growing on old wood, bark, Polyporus, etc. The stipe .4-.7 mm. in
length, the capillitium elongated 1.5-3 mm. Not uncommon, but it is
usually referred to _A. adnata_.
3. ARCYRIA ADNATA, Batsch. Sporangium ovoid; the calyculus very small,
finely ribbed and granulose. Stipe very short or entirely wanting.
Capillitium much expanded after dehiscence, globose or obovoid, pale red
to brownish in color; the threads uniform in thickness, about 4 mic.,
the surface with a series of prominent half-rings with mingled warts and
spines, which wind around the thread in a long spiral. Spores globose,
even, 6-8 mic. in diameter.
Growing in small clusters on old wood. A small species, the capillitium
expanded 1-2 mm., the stipe extremely short, or altogether absent.
4. ARCYRIA NUTANS, Bull. Sporangium cylindric; the calyculus small,
granulose, ribbed and sulcate. Stipe very short, arising from a common
hypothallus. Capillitium greatly elongated after dehiscence, cylindric,
drooping and pendulous, pale yellow or pale ochraceous; the threads 3-4
mic. in thickness, the surface covered with spinules, among which are
rings and half-rings, with an indistinct spiral arrangement. Spores
globose, even, 7-9 mic. in diameter.
Growing on old wood. The capillitium elongated 4-8 mm., the stipe very
short. A very conspicuous species by reason of its long pale yellow
capillitium.
Sec.2. PLECTANELLA. Capillitium erect, firmly attached by numerous threads,
which issue from the interior of the stipe, but are connate with the
wall of the calyculus, after dehiscence not much expanded: the meshes at
the surface of the network much smaller than those within, folded back
and forth, narrow and irregular, their threads densely warted or
spinulose; the meshes of the interior much larger, open and expanded,
their threads with minute scattered warts or perfectly smooth.
5. ARCYRIA CINEREA, Bull. Sporangium ovoid or oblong-ovoid; the
calyculus very small. Stipe long, erect, cinereous, becoming blackish,
standing on a thin hypothallus. Capillitium not much expanded after
dehiscence, ovoid-oblong, erect, pale cinereous, sometimes pale
yellowish; the external threads densely spinulose, 2-3 mic. in
thickness; the threads of the interior thicker, 3-5 mic., and very
minutely warted or quite smooth. Spores globose, even, 6-8 mic. in
diameter.
Growing on old wood. Capillitium 1-2 mm. long, the stipe about the same
length.
6. ARCYRIA COOKEI, Mass. Sporangium ovoid-cylindric, the calyculus very
small. Stipe long, erect, gray to mouse-color, darker below, arising
from a thin hypothallus. Capillitium not much expanded after dehiscence,
ovoid-cylindric, erect, gray to mouse-color; the superficial threads
densely and uniformly covered with minute warts, 3-5 mic. in thickness;
the threads of the interior thinner, about 2 mic. and smooth, or with
very minute scattered warts. Spores globose, even, 6-8 mic. in diameter.
See Plate I, Fig. 16.
Growing on old wood, mosses, etc. Capillitium 1-2 mm. long, the stipe
about the same length. It seems as common as _Arcyria cinerea_, and has
heretofore been included in it. See Massee's Monograph, p. 154.
7. ARCYRIA DIGITATA, Schw. Sporangium cylindric, the calyculus very
small. Stipe long, ascending, brownish in color, usually several
fasciculate or to some extent connate, the sporangia divergent at the
apex. Capillitium not much expanded after dehiscence, cylindric, pale
cinereous, or pale yellowish; the threads variable in thickness. 2-4
mic., those at the surface densely and minutely warted, those of the
interior nearly smooth. Spores globose, even, 6-8 mic. in diameter.
Growing on old wood. Capillitium 2-4 mm. long, the stipe about the same
length. _Arcyria bicolor_, B. & C.
III. HETEROTRICHIA, Massee. Sporangia regular, oblong-ovoid, stipitate;
the wall a thin delicate membrane, the upper part disappearing at
maturity, leaving the basal portion as a small calyculus. Stipe filled
with large thick-walled vesicles, which are sub-angular from mutual
pressure; these become smaller upward, and pass gradually into normal
spores. Capillitium issuing from the interior of the stipe, the central
and superficial threads dissimilar, forming a complicated network, with
numerous free extremities, the surface minutely warted, or with annular
ridges. Spores globose, brownish.
Distinguished from Arcyria by the numerous free extremities of the
peripheral portion of the network.
1. HETEROTRICHIA GABRIELLAE, Massee. Sporangium oblong-ovoid, stipitate;
the calyculus small, thin, smooth. Stipe very short, erect,
yellowish-brown in color. Capillitium much elongated after dehiscence,
cylindric-ovoid, sub-erect; the threads of the central portion about 1.5
mic. thick, with slightly elevated ridges partly encircling the tube,
nearly colorless; threads of the peripheral portion bright yellow, 5-6
mic. thick, with numerous short acute free branches, the surface densely
and minutely warted. Spores in mass, yellowish-brown, globose, even, 7-8
mic. in diameter. See Plate I, Fig. 18.
Growing on wood; S. Carolina, _H. W. Ravenel_. The sporangia densely
crowded, becoming scattered toward the margin of the cluster. Massee's
Monograph of the Myxogasters.
ORDER V. TRICHIACEAE.
Sporangium regular and stipitate or sessile, rarely plasmodiocarp; the
wall a thin membrane, usually granular or venulose on the inner surface,
colored as the spores and capillitium, irregularly dehiscent.
Capillitium of slender tubules, simple or branched, scarcely forming an
evident network; the surface of the threads furnished with continuous
ridges, which wind around the tube in a spiral manner. Spores globose,
red, brown, yellow, olivaceous.
This order is readily recognized by the spiral ridges which wind around
the tubules of the capillitium.
TABLE OF GENERA OF TRICHIACEAE.
1. HEMIARCYRIA. Capillitium of long slender tubules, arising from the
base of the sporangium, or issuing from the interior of the stipe; the
spiral ridges parallel and conspicuous.
2. CALONEMA. Capillitium of slender tubules, arising from the base of
the sporangium; the surface traversed by a system of branching veins.
3. TRICHIA. Capillitium consisting of numerous short slender tubules,
called elaters, which are wholly free; the spiral ridges parallel and
conspicuous.
4. OLIGONEMA. Capillitium scanty, composed of elaters habitually
irregular and abnormal; the surface variously marked.
I. HEMIARCYRIA, Fr. Sporangia regular and stipitate, rarely
plasmodiocarp, the wall at maturity breaking away from above downward,
leaving more or less of the lower portion persistent. Stipe more or less
elongated, rarely wanting, resting on a thin hypothallus. Capillitium of
long slender tubules, more or less branched, arising from the base of
the sporangium, or issuing from the interior of the stipe; the spiral
ridges parallel and conspicuous, 3-5, rarely more in number, smooth or
spinulose. Spores globose, red, yellow.
The genus is related on the one hand to Arcyria by the mode of
attachment of the threads, on the other hand to Trichia, by the parallel
spiral ridges which wind around them. By the mode of branching of the
threads, the species fall readily into two sections.
Sec.1. ARCYRIOIDES. Capillitium of slender threads, branching and
anastomosing, thus forming a more or less evident network.
In some of the species the large irregular meshes of the network are
scarcely to be discerned, but are rather to be inferred from the
abundant branching of the threads and the paucity of the free
extremities.
1. HEMIARCYRIA PLUMOSA, Morgan, n. sp. Sporangium obovoid to turbinate,
olive-yellow to olive-brown in color, stipitate; the wall densely
granulose within, externally smooth and shining, the upper part soon
disappearing, leaving a funnel-shaped persistent base. Stipe long,
erect, reddish-brown, arising from a thin hypothallus. Capillitium of
threads 5-7 mic. in thickness, repeatedly branched and anastomosing, to
form a dense network without any free extremities, olive-yellow to
olive-brown in color; the spiral ridges five or six, close, smooth.
Spores in mass, lemon-yellow, globose, very minutely warted, 8-9 mic. in
diameter. See Plate I, Fig. 19.
Growing gregariously on old damp logs; very common in this region.
Sporangium with the stipe 2-3 mm. in height, the stipe usually much
longer than the sporangium; the capillitium expands considerably after
the disappearance of the upper part of the sporangium. This species is
an Arcyria in every respect, except the spiral ridges, which wind about
the thread of the capillitium.
2. HEMIARCYRIA VARNEYI, Rex. Sporangium elongated ovoid, pale yellow,
stipitate; the upper part of the wall disappearing at maturity, leaving
a small cup-shaped persistent base. Stipe very short, dull brown.
Capillitium of very slender threads 3.2-3.5 mic. in thickness, dull
ochre in color, forming a network of small meshes, with numerous short
slightly clavate free extremities, which proceed from the peripheral
meshes; the spiral ridges seven or eight, winding unevenly, those of the
superficial threads minutely spinulose. Spores in mass pale yellow,
globose, even, 6-7 mic. in diameter.
Growing on old wood; Kansas, May Varney. Sporangium with the stipe about
1 mm. in height, the stipe very short. Dr. Rex, in Proceedings of the
Academy of Natural Sciences, Philadelphia, 1891.
3. HEMIARCYRIA ABLATA, Morgan n. sp. Sporangium obovoid to turbinate,
yellow or olive-yellow, stipitate; the wall rather firm, smooth and
shining, breaking away about the apex, leaving the greater portion
persistent. Stipe short, erect, yellow-brown to blackish in color,
arising from a thin hypothallus. Capillitium of threads, 5-7 mic. in
thickness, yellowish-ochre in color, more or less branched; the free
extremities very scarce, obtuse or slightly swollen; the spiral ridges
four or five, close, smooth or very minutely warted. Spores in mass,
yellow, globose, minutely warted, 8-9 mic. in diameter.
Growing on old wood of Elm, etc. Sporangium with the stipe 1.5-2.5 mm.
in height, the stipe variable in length, but not longer than the
sporangium, diameter of the sporangium .6-.8 mm. A half dozen threads
proceed from the inner wall of the stipe branch twenty-five or thirty
times, and afford scarcely half a dozen free ends.
4. HEMIARCYRIA STIPATA, Schw. Sporangia terete, elongated and flexuous,
closely packed together and lying upon one another, stipitate, from
bright incarnate to brick red or bay in color, smooth and shining; the
wall thin and fragile, soon disappearing, except a small cup-shaped
portion at the base. The stipes very short, often entirely concealed by
the dense mass of sporangia, arising from a common hypothallus.
Capillitium of threads somewhat variable in thickness, 3-6 mic.,
repeatedly branched and forming a network of very unequal meshes, with
occasional clavate free extremities, pale to dark red in color; the
spiral ridges three or four, often irregular, thickened or interrupted
by minute warts and spinules. Spores in mass incarnate to brownish-red,
globose, even, 7-9 mic. in diameter.
Growing on old wood of Liriodendron. Sporangia usually in small patches,
each 1-2 mic. in length, the stipe very thin and short.
Sec.2. HEMITRICHIA. Capillitium of very long slender threads, simple or
remotely branched, and not forming a network, their further extremities
all free.
The threads of the capillitium in these species are usually much coiled
and entangled, but when straightened out they are seen to be very long,
but few in number, fixed at one end and free at the other.
5. HEMIARCYRIA LONGIFILA, Rex. Sporangium obovoid or pyriform, yellow,
stipitate; the wall a thin pellucid membrane, smooth and shining,
beautifully iridescent, breaking away above the middle, the lower
cup-shaped portion persistent. Stipe very short, reddish-brown to
blackish, arising from a common hypothallus. Capillitium of slender
threads, 3.5-4 mic. in thickness, golden yellow in color, simple or very
rarely branched; the free extremities obtuse or slightly swollen,
sometimes minutely apiculate; the spiral ridges, three or four, rather
distant, with very minute scattered spinules or nearly smooth. Spores in
mass, golden-yellow, globose, minutely warted, 9-10 mic. in diameter.
Growing on old wood of Oak, etc. Sporangium with the stipe .8-1.5 mm. in
height, the stipe very short, not exceeding the diameter of the
sporangium. A small species, distinguished by its golden-yellow spores
and capillitium.
6. HEMIARCYRIA FUNALIS, Morgan n. sp. Sporangium obovoid to turbinate,
yellow or olive yellow, polished stipitate; the wall firm, thickened on
the inner surface by an olivaceous layer, breaking away from above
downward, leaving an irregular cup-shaped base. Stipe short,
reddish-brown to blackish, arising from a thin hypothallus. Capillitium
of threads 6-8 mic. in thickness, yellowish-ochre or dull ochre in
color, simple or remotely branched; the free extremities obtuse or
swollen; the spiral ridges four or five, minutely warted. Spores in mass
yellow, globose, minutely warted, 8-9 mic. in diameter. See Plate I,
Fig. 20.
Growing on old wood. Sporangium 1.5-2.5 mm. in height, the stipe
variable, but usually much shorter than the sporangium. Scarcely to be
distinguished from _Hemiarcyria ablata_, except by the threads of the
capillitium.
7. HEMIARCYRIA RUBIFORMIS, Pers. Sporangium obovoid or turbinate to
cylindric, usually few to many fasciculate upon the united stipes,
sometimes sessile, brown-red to brown or blackish in color, smooth and
often shining with a metallic luster; the wall much thickened by a dense
brownish-red layer of minute granules, at maturity the apex torn away,
leaving much the greater part persistent. Capillitium of slender
threads, 4-6 mic. in thickness, brownish-red in color, very rarely
branched; the free extremities usually terminated by a stout spine; the
spiral ridges three or four, furnished with numerous spinules. Spores in
mass, brownish-red, globose, minutely warted, 9-11 mic. in diameter.
Growing on old wood; one of the commonest of the Myxomycetes. The
fascicle 3-4 mm. in height, the individual sporangia .5-.6 mm. in
diameter.
8. HEMIARCYRIA SERPULA, Scop. Plasmodiocarp terete, flexuous, usually
branching and anastomosing to form an extensive network, from tawny to
golden-yellow in color; the wall thin above and yellow, breaking open
irregularly and falling away down to the brownish thicker adherent
base. Capillitium consisting of a few long slender threads with
numerous scattered short branches, the threads 4-6 mic. in thickness,
golden-yellow; the free ends of the branches terminating in a slender
spine; the spiral ridges three or four, covered with numerous slender
spinules. Spores in the mass golden-yellow, globose, the surface
reticulate, 10-12 mic. in diameter.
Growing on and inside of rotten wood. Plasmodiocarp an irregular patch,
one to several centimeters in extent, the strands of the net about .5
mm. in thickness. A single reticulate plasmodium is usually converted
without change of form into an individual plasmodiocarp.
II. CALONEMA, Morgan, gen. nov. Sporangia subglobose, irregular,
sessile, without a hypothallus; the wall thin, marked with branching
veins, irregularly dehiscent. Capillitium of slender tubules, arising
from the base of the sporangium, repeatedly branched and with numerous
free extremities; the surface traversed by a system of branching veins,
ending in minute veinlets, which appear as irregular rings and spirals.
Spores subglobose, yellow.
The habit of the single species is that of an Oligonema, and it has
spores similar to those of most species of this genus, but the threads
are long and branched, and they are fastened below to the base of the
sporangium.
1. CALONEMA AUREUM, Morgan n. sp. Sporangia subglobose to turbinate,
sessile, closely crowded and from mutual pressure quite irregular; the
wall thin, marked with branching veins, golden-yellow in color, smooth
and shining. Capillitium of threads more or less branched, 5-6 mic. in
thickness, golden-yellow; the surface minutely venulose, and with larger
rings and spirals, and sometimes with scattered spinules; the free
extremities obtuse. Spores subglobose, yellow, the surface with elevated
ridges combined into a network, 14-16 mic. in diameter. See Plate I,
Fig. 21.
Growing on and within rotten wood. Sporangia quite irregular and
variable in size, .3-.6 mm. in diameter. The beautiful venation of the
wall of the sporangium is continued upon the surface of the threads of
the capillitium.
III. TRICHIA, Haller. Sporangia regular and stipitate or sessile and
somewhat irregular; the wall, at maturity, irregularly ruptured. The
stipe more or less elongated or often wanting, usually resting on a
hypothallus. Capillitium consisting of numerous short slender tubules,
called _elaters_, intermingled with the spores and wholly free; elaters
simple or rarely branched a time or two, each extremity terminating in a
smooth tapering point; the spiral ridges parallel and conspicuous, 2-5
in number, smooth or spinulose. Spores globose, yellow, ochraceous,
olivaceous.
The genus Trichia is unique among the Myxomycetes in having its
capillitium composed of tubules, which are entirely free from the wall
of the sporangium. The length of these free tubes varies usually between
.3 mm. and .5 mm., being sometimes shorter, but seldom longer; they are
typically cylindric, or equally thickened from end to end, or quite
rarely they are thickened in the middle, and taper gradually to each
extremity; the extremities terminate in a smooth tapering point,
straight or sometimes a little curved or flexuous, which maintains an
average length in each species. The spiral ridges wind around the thread
almost invariably to the left, or with the hands of a watch; they are
always more or less prominent and conspicuous, and usually maintain a
regular curve and uniform interval between each other in the same
species; their surface is either smooth, or sometimes it is invested
with minute warts or spinules.
In all the species of this genus, however, irregular and abnormal
elaters are occasionally met with among the typical ones. As these
abnormal forms always arrest attention, and have been conceived to
possess specific value, it may be well to note the principal of them.
1. The elater is sometimes branched. In two or three species the
branching appears to be quite regular and not abnormal; still, even in
these species, most of the elaters in the sporangia are not branched. In
some cases the branching arises from confluence of two or more elaters.
2. Ellipsoidal swellings, or enlargements of the elater, sometimes
occur, at one or both extremities, or at points intermediate between
them; these always occur irregularly, and are essentially abnormal.
3. The smooth tapering point is rarely wanting, in which case the
extremity presents a blunt end, the spiral ridges running to the end.
More frequently the tapering points are multiplied, the elaters bearing
two or three spines at the extremities; this often occurs in the species
of Trichia, and also of Hemiarcyria with spinulose elaters.
4. The spiral ridges are sometimes defective, there being less than the
typical number; sometimes they are merely displaced, there being a much
wider interval between them than usual; rarely do they habitually wind
about the thread in an irregular manner.
5. Under high magnifying power, fine ridges are sometimes seen running
lengthwise of the elaters, bridging the intervals between the spirals.
These were first observed by DeBary, in _Trichia chrysosperma_, but they
have since been seen in the elaters of nearly every other species of
Trichia, and also in species of Hemiarcyria.
The few species with elaters, so far as yet known, habitually irregular,
defective and abnormal, are referred to the genus Oligonema.
The normal species of Trichia arrange themselves quite naturally into
three sections.
Sec.1. A NACTIUM. Sporangia varying from globose to pyriform or turbinate,
supported on a more or less elongated stipe. Spores globose, the surface
minutely warted.
_a. Elaters with very long tapering extremities._
1. TRICHIA FRAGILIS, Sow. Sporangia obovoid to pyriform or clavate,
often fasciculate, stipitate; the wall a thin membrane, with a thick
dense outer layer of brown-red granules. Stipes long, erect or curved,
simple or usually fasciculate and often connate, arising from a thin
hypothallus. Mass of spores and capillitium from reddish-brown to yellow
and ochraceous; elaters simple, rarely branched, 4-5 mic. thick, with
very long tapering extremities, ending in smooth points 8-12 mic. long;
spirals, three or four, perfectly smooth. Spores globose, minutely
warted, 10-12 mic. in diameter.
Growing on old wood. Sporangia with the stipe 2-4 mm. in height, the
sporangium .6-.8 mm. in diameter, the stipe usually longer than the
sporangium. The color quite variable, mostly dull red-brown or
blackish-brown, more rarely yellow or coffee-brown, usually opaque,
rarely shining.
2. TRICHIA FALLAX, Pers. Sporangium obovoid to pyriform or turbinate,
rarely clavate, stipitate; the wall thin, smooth and shining, colored as
the spores and capillitium. Stipe more or less elongated, simple, erect,
brownish below, filled with roundish vesicles. Mass of capillitium and
spores yellowish, ochraceous or olivaceous; elaters simple or sometimes
with several branches, 4-6 mic. thick in the middle, tapering gradually
to each extremity, ending in smooth tapering points, 20-40 mic. in
length; spirals, three, perfectly smooth. Spores globose, minutely
warted, 10-12 mic. in diameter. See Plate I, Fig. 22.
Growing on old wood. Sporangium with the stipe 2-4 mm. in height,
sporangium .6-.8 mm. in diameter, the stipe usually longer than the
sporangium. Under high magnifying power the spores are seen to be
minutely reticulated.
_b. Elaters cylindric, ending in a smooth tapering point._