Sporangia simple and stipitate or sessile, sometimes plasmodiocarp, rarely combined into an aethalium; the wall a thin membrane, usually with an outer layer of minute roundish granules of lime. Stipe present or often wanting, seldom prolonged within the sporangium as a columella. Capillitium consisting of slender tubules, which branch repeatedly in every direction and anastomose to form an intricate network, the extremities attached on all sides to the wall of the sporangium; the tubules more or less expanded at the angles of the network and inclosing minute roundish granules of lime, these granules either aggregated into nodules with intervening empty spaces or more rarely distributed throughout their entire length. Spores globose, very rarely ellipsoidal, violaceous.

This order is at once distinguished from the DidymiaceÆ by the presence of the granules of lime in the capillitium.

Table of Genera of PhysaraceÆ.

I. Tubules of the capillitium having the granules of lime in them aggregated into roundish or angular nodules, with intervening empty spaces.

A. Outer surface of the sporangium destitute of lime.

• 1. Angioridium. Plasmodiocarp laterally compressed, splitting regularly into two valves.
• 2. Cienkowskia. Plasmodiocarp terete, elongated, irregularly dehiscent.
• 3. Leocarpus. Sporangia subglobose or obovoid, stipitate or sessile.

B. Outer surface of the sporangium invested with granules of lime.

a. Stipe prolonged within the sporangium as a columella.

• 4. Physarella. Sporangium oblong, stipitate, the apex re-entrant.
• 5. Cytidium. Sporangium globose, stipitate, the apex convex.

b. Stipe never entering the sporangium.

• 6. Craterium. Sporangium obovoid to cylindric, stipitate.
• 7. Physarum. Sporangium globose, depressed globose or irregular, stipitate or sessile.
• 8. Fuligo. Aethalium a compound plasmodiocarp.

II. Tubules of the capillitium with the granules of lime in them distributed throughout their entire length.

• 9. Badhamia. Stipe not prolonged within the sporangium as a columella.
• 10. Scyphium. Stipe entering the sporangium and prolonged within it as a columella.

I. ANGIORIDIUM Grev. Plasmodiocarp laterally compressed, more or less elongated and flexuous, attached by the lower margin to the substratum, and, at maturity, regularly dehiscent along the upper margin by a longitudinal fissure; the wall a firm membrane, with the granules of lime forming a reticulate layer on the inner surface. Capillitium a loose, irregular net-work of tubules, extending from side to side, and containing large, irregular nodules of lime. Spores globose, violaceous.

A genus readily distinguished by its laterally compressed plasmodiocarp, splitting lengthwise by a regular fissure. The wall is a single membrane, and there is but a single reticulate layer of lime upon it, which is plainly on the inner surface.

1. Angioridium sinuosum Bull. Plasmodiocarp laterally compressed and very much flattened, more or less elongated and flexuous, sometimes confluent and branched or reticulate, without any hypothallus; the wall a more or less thickened and brownish membrane, the inner surface coated with a dense reticulately thickened white layer of lime, and often studded with the white nodules. Capillitium of hyaline tubules, forming a loose irregular net-work, with numerous broad vesicular expansions filled with lime; the nodules white, very large, irregularly lobed, and branched. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old leaves, sticks, mosses, etc. Plasmodiocarp commonly about 1 mm. in height and 1–5 mm. in length, but the size is variable. The color appears to depend upon the thickening of the membrane; when it is thin and pellucid, the color is white or cinereous from the inner layer of lime and the contained spores; with a more thickened membrane, the color becomes ochraceous or brownish. Physarum bivalve Pers. Physarum sinuosum of Rostafinski's monograph. See Plate XIII. Fig. 49.

II. CIENKOWSKIA Rost. Plasmodiocarp terete, elongated, flexuous, creeping, and reticulate, irregularly dehiscent; the wall a more or less thickened membrane, externally naked, with the granules of lime on the inner surface. Capillitium of slender tubules, combined into an irregular network, attached on all sides to the wall of the sporangium, and bearing everywhere short pointed or uncinate free branchlets; the lime in thin transverse plates and irregular nodules. Spores globose, violaceous.

The peculiar characteristic of this genus is the short free hooked and pointed branchlets of the capillitium.

1. Cienkowskia reticulata A. & S. Plasmodiocarp more or less elongated, curved and flexuous, simple or branched, sometimes confluent and reticulate, breaking away first along the upper surface, leaving an irregular margin. The wall a firm yellow membrane, with thinner hyaline areas and with thicker yellow-brown or red-brown spots; the outer surface without any lime, smooth, and shining; the inner surface with a dense layer of yellow granules raised at intervals into transverse ridges, these are connected with broad thin flat plates of lime which traverse the capillitium, forming imperfect septa to the sporangium. Capillitium consisting of slender yellow tubules, forming a network of irregular meshes, with slight expansions at the angles and bearing along the sides short pointed or uncinate free branchlets; the tubules containing a few scattered yellow nodules of lime various in size and shape. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old wood, bark, leaves, etc. Plasmodiocarp in veins .3-.5 mm. in thickness, sometimes forming a net-work a centimeter or more in extent. This curious Myxomyces seems very rare in America. I have met with it but once. The specimen in the herbarium of Schweinitz, marked Physarum reticulatum, is not this species, though it answers well enough to the original description. See Plate XIII. Fig. 50.

III. LEOCARPUS Link. Sporangia subglobose or obovoid, stipitate or sessile; the wall a more or less thickened membrane, the external surface destitute of lime, polished and shining, irregularly dehiscent. Stipe short, poorly developed or sometimes wanting. Capillitium of slender tubules, forming an irregular net-work more or less expanded at the angles; the tubules enlarging at intervals into vesicles, which usually contain nodules of lime. Spores globose, violaceous.

A genus characterized by the form of the sporangia and the smooth and glossy surface of the wall.

1. Leocarpus psittacinus Ditm. Sporangium small globose or somewhat depressed, stipitate or subsessile; the wall a thin membrane, rugulose and iridescent, with thicker red or yellow spots and patches, destitute of lime. Stipe weak, erect or inclined, variable in length, the base expanded, orange to red in color. Capillitium a dense net-work of tubules, widely expanded at the angles and bearing numerous irregular vesicles, various in size and form, yellow or orange to red in color. Spores globose, even, dark violaceous, 7–9 mic. in diameter.

Growing on old wood, leaves, etc. The sporangium .5-.6 mm. in diameter, the stipe about the same length or sometimes very short. The sporangia are dull brownish to the naked eye, but when magnified the green, purple, and blue metallic tints of the wall become apparent. There does not appear to be any granules of lime either on the wall or in the capillitium. Physarum psittacinum Ditm.

2. Leocarpus cÆspitosus Schw. Sporangium small subglobose or obovoid to turbinate, somewhat irregular, stipitate or subsessile; the wall a reticulately thickened and fragile membrane, yellow-brown to greenish-yellow or olivaceous in color, externally rugulose and glossy, the inner surface with scales and patches of lime. Stipe short and thick, sometimes nearly obsolete, yellowish or reddish brown, darker below, the base expanded into a small hypothallus. Capillitium a loose irregular net-work of tubules with wide expansions at the angles; the nodules of lime large, numerous, white or yellowish, irregular, with acute angles and pointed lobes. Spores globose, minutely warted, dark violaceous, 9–11 mic. in diameter.

Growing cÆspitosely or scattered on old wood and mosses. Sporangium .6-.8 mm. in diameter, variable in shape, the stipe usually very short. Physarum cÆspitosum Schw., North American Fungi. My specimens, some of them, have been referred to Physarum citrinellum Peck; others to Physarum variabile Rex. See Plate XIII. Fig. 52.

3. Leocarpus brunneolus Phillips. Sporangium large, globose or somewhat depressed, sessile; the wall a thick yellow-brown membrane, the outer surface naked, smooth, and polished, with a dense white inner layer of granules of lime, dehiscing in a stellate manner, the segments becoming reflexed. Capillitium of tubules forming a dense net-work, with wide expansions at the angles; the nodules of lime very large, numerous, white, angular and irregular. Spores globose, minutely warted, dark violaceous, 8–10 mic. in diameter.

Growing on bark of oak, California (Harkness.) Sporangium nearly 1 mm. in diameter. Diderma brunneolum Phillips. I have taken the description from Massee's monograph.

4. Leocarpus fragilis Dicks. Sporangium very large, obovoid-oblong, stipitate or subsessile; the wall a greatly thickened membrane, polished and shining within and without, from alutaceous or pale umber to dark-brown in color, destitute of lime. Stipe short, weak, and slender, arising from a thin hypothallus. Capillitium of slender tubules forming a loose network of large irregular meshes, with slight expansions at the angles; the lime white, variable in amount, sometimes quite scanty, then again filling large portions of the net-work with long-branched and reticulate masses. Spores subglobose, dark violaceous, opaque, 12–15 mic. in diameter.

Growing gregariously on old wood, leaves, mosses, etc. Sporangium 1.5–2 mm. in length by 1 mm. in thickness, the stipe variable in length, but usually much shorter than the sporangium. Diderma vernicosum Pers. See Plate XIII. Fig. 51.

IV. PHYSARELLA Peck. Sporangium oblong, stipitate; the apex re-entrant and confluent with the hollow columella; the wall a thin membrane covered with small scales and minute granules of lime, at maturity torn away at the apex and stellately splitting into a few segments. Stipe elongated, tapering upward, entering the sporangium and prolonged to the apex as a tubaeform columella. Capillitium distinguished by two distinct sets of tubules; the first consisting of long, thick tubules filled with lime, rising at regular intervals from the wall of the sporangium and extending to the columella; the second, of very slender threads, scarcely branched, and nearly destitute of lime, stretching between the wall and the columella. Spores globose, violaceous.

A genus founded upon the one remarkable species, and more distinct than any other from the typical genus of the Physaraceae. In fact, the structure of the sporangium is unique among the Myxomycetes.

1. Physarella oblonga B. & C. Sporangium oblong, the apex re-entrant and confluent with the summit of the columella, the base obtuse or slightly umbilicate, stipitate, cernuous. The wall of the sporangium a firm, yellowish membrane, covered with minute granules and with scattered, small, yellow scales of lime; after maturity the apex is torn away more or less irregularly from the summit of the columella and the wall splits into a few segments, which become reflexed and are subpersistent about the base of the sporangium. Stipe long, erect or flexuous, the apex bent or curved, red-brown, rising from a small hypothallus, entering the sporangium and prolonged to the apex as a hollow tubaeform columella. Capillitium of thick, spiniform tubules filled with lime and slender, violet threads, extending between the wall and the columella. The tubules elongated, terete, tapering gradually from wall to columella, containing yellow granules of lime; the threads very slender, outwardly branched a time or two, the further extremities connected by short, lateral branches, often furnished with minute, free branchlets, and containing a few small, fusiform nodules of lime. Spores globose, nearly smooth, violaceous, 7–9 mic. in diameter.

Growing on old wood, bark, leaves, etc. Sporangium commonly .8–1.0 mm. in length by .5-.6 mm. in diameter, the stipe 1–2 mm. long; the spiniform tubules measure 150–200 × 15–20 mic. See Plate XIII. Fig. 53.

The abnormal forms of this species which sometimes manifest themselves are very singular; the sporangium has a tendency to dilate, becoming funnel-form or even salver-shaped, the stipe shortening and even disappearing. I have a large specimen which superficially resembles some lichen, a Physcia, for example; the sporangia are pressed down, flattened out, extremely irregular, and in many places confluent; the rudimentary stipes are hidden beneath the leafy expansions. In all the forms, however, may be uncovered the spiniform tubules mingled with the slender threads. This is Trichamphora oblonga B. & C. Tilmadoche oblonga of Rostafinski's monograph, and Physarella mirabilis Peck.

V. CYTIDIUM Morgan. Gen. nov. Sporangium globose or rarely ellipsoidal, stipitate; the wall a thin membrane, with an external layer of minute granules of lime, rupturing irregularly. Stipe more or less elongated, tapering upward and entering the sporangium as a columella. Capillitium of slender tubules, arising from the columella, repeatedly branching and anastomosing to form a regular net-work, the extremities attached on all sides to the wall of the sporangium, the tubules containing at intervals nodules of lime. Spores globose, violaceous.

This genus is readily distinguished from Physarum by the columella, which gives origin to the capillitium; this feature indicates a relationship to Didymium and to Lamproderma.

§1. Eucytis. Sporangium globose, the columella not reaching its center.

1. Cytidium pulcherrimum B. & R. Sporangium globose, stipitate; the wall a thin lilac-tinted membrane, with a dense closely adherent layer of granules of lime, dark purple or wine-colored. Stipe long, erect, dark purple to purplish black, tapering upward and entering the sporangium as a slight obtuse columella. Capillitium of slender lilac tinted threads, forming a dense net-work of very small meshes, with slight expansion at the angles; the nodules of lime very small, numerous, dark purplish or vinose in color, ellipsoidal or obtusely angular. Spores globose, even, lilac, 7–9 mic. in diameter.

Growing on old wood. Sporangium .4-.5 mm. in diameter, the stipe two or three times as long; the lime-nodules about the size of the spores. The purple stain, which the sporangia leave on white paper, is made by the granules of lime; the spores color the paper violet. Physarum pulcherrimum B. & Rav., and P. atrorubrum Peck.

2. Cytidium citrinum Schum. Sporangium globose, the base slightly flattened or umbilicate, stipitate; the wall a thin membrane, covered with small scales of lime, yellow or greenish-yellow, breaking up and falling away at maturity. Stipe stout, erect, yellow, longitudinally rugulose, expanded at the base, tapering upward and entering the sporangium as a short obtusely conical columella. Capillitium of slender tubules, forming a dense net-work, with slight expansions at the angles; the lime-nodules numerous, roundish or ellipsoidal, variable in size, yellow. Spores globose, nearly smooth, violaceous, 7–8 mic. in diameter.

Growing on bark, leaves, mosses, etc. Sporangium .5-.6 mm. in diameter, the stipe from once to twice this length. This, the typical species, I have not seen in this country, but forms with the sporangium lemon-yellow and grayish-yellow, with the stipe golden-yellow, connect it with C. rufipes. It is Physarum citrinum Schum. Diderma citrinum of Fries., S. M.

3. Cytidium rufipes A. & S. Sporangium globose, sometimes a little depressed and the base umbilicate, stipitate; the wall a thin membrane, covered with small scales of lime, golden-yellow to orange in color, breaking up at maturity and falling away. Stipe variable in length, slender, from orange or orange-red to dark red in color, sometimes blackish below, rising from a thin hypothallus, tapering upward and entering the sporangium as a short obtuse columella. Capillitium of slender tubules, forming a dense net-work of very small meshes, slightly expanded at the angles; the nodules of lime small, numerous, ellipsoidal or obtusely angular, orange to red in color. Spores globose, nearly smooth, violaceous, 8–10 mic. in diameter.

Growing on old wood, mosses, etc. A very abundant species. Sporangium .5-.7 mm. in diameter, the stipe from once to twice as long. As here defined, the species includes Physarum aurantium var. rufipes A. & S., and Physarum aureum var. chrysopus Lev, which I am unable to keep separate; the variation in size of the spores is not in correspondence with the variations in color of the sporangia. Physarum pulchripes Peck, and Physarum petersii B. & C., mostly belong here. The bright orange colors become dull or tawny with age and exposure to the weather.

4. Cytidium ravenelii B. & C. Sporangium globose, stipitate; the wall a thin pellucid membrane, covered with small scales of lime, from gray or drab to pale umber in color, breaking up at maturity and falling away. Stipe variable in length, concolorous with the sporangium or darker below, tapering upward and entering the sporangium as a short obtusely conical columella. Capillitium of tubules, forming a dense net-work of very small meshes, with slight expansions at the angles; the lime-nodules small, numerous, ellipsoidal or obtusely angular, gray or drab to pale umber in color. Spores globose, nearly even, pale violaceous, 7–9 mic. in diameter.

Growing on old wood, mosses, etc. Sporangium about .5 mm. in diameter, the stipe once to twice this length. The species as here described includes Didymium ravenelii B. & C., Physarum simile Rost., and Physarum murinum Lister.

5. Cytidium globuliferum Bull. Sporangium globose, the base sometimes flattened or slightly umbilicate, stipitate; the wall a thin, pellucid membrane, covered with small scales of lime, white, cream-colored, or sometimes pinkish, breaking up and falling away at maturity. Stipe variable in length, white or smoky-white, usually darker below, rising from a thin hypothallus, tapering upward and entering the sporangium as a short obtuse or conical columella. Capillitium of slender tubules, forming a dense, persistent net-work of very small meshes, more or less expanded at the angles; the nodules of lime variable in size, numerous, white, roundish, ellipsoidal or obtusely angular. Spores globose, nearly even, pale violaceous, 7–9 mic. in diameter.

Growing on old wood, bark, mosses, etc. A very common and abundant species. Sporangium .5-.6 mm. in diameter, the stipe from once to two or three times this length. The lime nodules in the capillitium are sometimes round and quite minute, then again they are large and obtusely angular; the columella varies from very short and conical to longer and more cylindric. Diderma globuliferum of Fries S. M., Physarum albicans Peck. The specimens with the columella well nigh obsolete, may be Tilmadoche columbina Rost. See Plate XIII. Fig. 55.

6. Cytidium melleum B. & Br. Sporangium globose, stipitate or subsessile; the wall a thin yellowish membrane, rugulose, covered by large irregular scales of lime, honey-color to golden-yellow, breaking up irregularly. Stipe short, sometimes very short or nearly obsolete, snow-white, expanding at the base into a small white hypothallus, tapering upward and entering the sporangium as a short obtusely conical columella. Capillitium a loose net-work of delicate tubules with broad vesicular expansions containing much lime; the nodules numerous, white or sometimes yellow, large, irregular, lobed, and branched. Spores globose, nearly even, pale violaceous, 7–9 mic. in diameter.

Growing on old leaves, sticks, herbaceous stems, etc.; not uncommon in this region. Sporangium .4-.5 mm. in diameter, the stipe about the same length or much shorter. Didymium melleum B. & Br. Didymium chrysopeplum B. & C. also belongs here and not with C. citrinum.

§2. Rexiella. Sporangium ellipsoidal or pyriform, the columella prolonged nearly to the apex of the sporangium.

7. Cytidium penetrale Rex. Sporangium ellipsoidal or pyriform, stipitate; the wall a thin pellucid membrane, covered with small scales of lime, yellow-gray to greenish-yellow, rupturing at maturity into two to four segments. Stipe long, slender, translucent, pale red to dark red in color, tapering upward, entering the sporangium and prolonged nearly to the apex as a slender columella. Capillitium of very slender tubules, radiating from numerous points of the columella, forming a delicate net-work of very small meshes, scarcely expanded at the angles; the nodules of lime small, not numerous, roundish or obtusely angled, white or yellowish. Spores globose, very minutely warted, pale violaceous, 5.5–6.5 mic. in diameter.

Growing on old wood. A rare and singular species. Sporangium .5-.7 mm. in height by .3-.5 mm. in diameter, the stipe two or three times the height of the sporangium. There is an affinity between this species and the Physarella. The obscure Tilmadoche hians Rost., may be the same as the present species. See Plate XIII. Fig. 54.

EXPLANATION OF PLATE XIII.

• Fig. 49.—Angioridium sinuosum Bull. a. Plasmodiocarp × 5 b. Capillitium and spores × 500.
• Fig. 50.—Cienkowskia reticulata A. & S. a. Plasmodiocarp × 5. b. Piece of plasmodiocarp × 90. c. Capillitium and spores × 500.
• Fig. 51. Leocarpus fragilis Dicks, a. Sporangia × 5. b. Capillitium and spores × 500.
• Fig. 52.—Leocarpus caespitosus Schw. a. Sporangia × 5. b. Capillitium and spores × 500.
• Fig. 53.—Physarella oblonga B. & C. a. Sporangia × 5. b. Sporangia × 90. c. Capillitium and spores × 500.
• Fig 54—Cytidium penetrale Rex. a. Sporangia × 5 b. Sporangia and columella × 90. c. Capillitium and spores × 500.
• Fig. 55.—Cytidium globuliferum Bull. a. Sporangia × 5. b. Sporangia × 90. c. Columella × 90 d. Capillitium and spores × 500.

VI. CRATERIUM Trent. Sporangium obovoid to cylindric, stipitate; the upper and usually greater part of the wall covered with granules of lime, the basal portion naked and more persistent. Stipe short or sometimes elongated, arising from a small circular hypothallus, longitudinally plicate, confluent above and similarly colored with the base of the sporangium. Capillitium of tubules, forming a loose network, bearing numerous large angular and irregular nodules of lime, which are often confluent along the axis of the sporangium into a pseudo-columella. Spores globose, minutely warted, violaceous.

In this genus the sporangium is commonly obovoid, with a naked base which is confluent with the stipe and similarly colored; after dehiscence there is left behind the more persistent cyathiform portion standing on the substratum.

§1. Eu-Craterium. Sporangium at maturity dehiscent in a regular circumscissile manner, the apex falling away as a lid, leaving behind the more persistent cup-shaped portion.

1. Craterium minutum Leers. Sporangium cyathiform, stipitate; the lid slightly convex, discrete from the first, usually depressed below the rim of the cup, falling away at maturity, and leaving a smooth, circular margin to the lower cyathiform portion. The wall a thick, firm, yellow-brown membrane, the outer surface of the cup entirely naked, smooth and shining, varying greatly in color from alutaceous or ochraceous to various shades of brown; the lid usually whitened by a thin layer of granules of lime. Stipe short, erect or bent, and slightly curved at the apex, varying in color from rusty yellow to reddish brown, longitudinally plicate, arising from a small, circular hypothallus. Capillitium of tubules forming a loose net-work, bearing large, irregular, white nodules of lime, which are sometimes confluent in the axis of the sporangium. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old wood, sticks, leaves, etc. Sporangium, together with the stipe, .8–1.4 mm. in height and .3-.5 mm. in diameter, the stipe usually shorter than the sporangium, sometimes equal to it in length, rarely longer. The latest authorities include the three species Craterium vulgare, C. pyriforme, and C. minutum of Rostafinski's monograph all in one species.

2. Craterium concinnum Rex. Sporangium usually minute, broadly funnel-shaped, stipitate; operculum always more or less convex, rarely approaching a hemispherical shape, dehiscent in a regular circumscissile manner. The wall a thick, brownish membrane, externally smooth and variously colored, sometimes uniformly light or dark umber, sometimes dark brown below and brownish white above; the operculum brownish white, darkest in the center. Stipe short, dark brown, longitudinally ridged. Capillitium of tubules forming a close-meshed net-work, bearing small rounded or slightly angular nodules of lime, ochre-brown in color. Spores globose, very minutely warted, brown, 9–10 mic. in diameter.

Growing usually upon chestnut-burs, and frequently associated with Lachnobulus globosus. Sporangium .5-.8 mm. in height including the stipe and .2-.5 mm. in diameter at the top, the stipe equaling the sporangium in length. It is readily distinguished by its small nodules in the capillitium, which are invariably of a dull, brownish-ochre color.

3. Craterium rubescens Rex. Sporangium subcylindric or elongated cyathiform, stipitate; the apex convex, at maturity separating by an irregular line in a circumscissile manner. The wall dark violet-red, smooth, except at the upper portion, which is slightly roughened by an external deposit of scattered lime-granules of a pale, lilac color. Stipe short, violet-black, wrinkled longitudinally. Capillitium of tubules forming a loose, irregular net-work, bearing large, violet-red nodules of lime which are often confluent in the axis of the sporangium. Spores globose, minutely warted, dark violaceous, 7–9 mic. in diameter.

Growing on old wood, leaves, etc. Sporangium .6-.8 mm. in height including the stipe and .5-.6 mm. in diameter, the stipe one-half the height of the sporangium. The species is distinguished by the color, which exhibits some shade of red or violet-red in every part of its structure.

4. Craterium minimum B. & C. Sporangium cylindric or turbinate cylindric, stipitate; the apex convex, separating in a regular circumscissile manner by a lid. The wall a thick, yellow-brown membrane, most of the outer surface covered with minute, white granules of lime, the basal portion naked. Stipe very short, plicate, red-brown, arising from a small hypothallus. Capillitium of tubules forming a loose net-work bearing large, irregular, white nodules of lime, sometimes confluent in the axis of the sporangium. Spores globose, very minutely warted, violaceous, 7–9 mic. in diameter.

Growing on old leaves, herbaceous stems, etc. Sporangium together with the stipe 1–1.5 mm. in height and .25-.35 mm. in thickness, the stipe .2-.4 mm. in length. This is a common species everywhere in the United States, and perfectly distinct from Craterium convivale. It is Craterium cylindricum of Massee's monograph, according to Lister. See Plate XIV. Fig. 56.

§2. Cupularia, Link. Sporangium irregularly dehiscent, breaking up and gradually falling away from the apex downward.

a. Stipe shorter than the sporangium.

5. Craterium convivale Batsch. Sporangium obovoid or oblong-obovoid, stipitate; the wall hyaline, thin and fragile above, the lower portion a thickened and brownish membrane, the surface, usually most of it, covered with minute white granules of lime, the base naked and brown. Stipe very short, erect, red-brown, plicate, arising from a small hypothallus. Capillitium of tubules forming a dense net-work, bearing numerous large irregular white nodules of lime, which are often confluent in the axis of the sporangium. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old leaves, herbaceous stems, etc. Sporangium .6–1.0 mm. in height including the stipe and .3-.5 mm. in diameter, the stipe much shorter than the sporangium. The thin apex breaks up into pieces and falls away, leaving sometimes a regular cyathiform portion, at other times the margin is broken and irregular. This is Craterium leucocephalum of Rostafinski's monograph. The specimens of Physarum scyphoides C. & B. which I have seen appear to be a small form of this species.

6. Craterium aureum Schum. Sporangium obovoid to oblong obovoid, stipitate, the wall a thin and delicate membrane above, thicker and firmer below, hyaline or yellowish, almost entirely covered by a dense layer of granules of lime, varying from lemon-yellow to orange in color. Stipe short, erect, yellow to orange, brownish toward the base, longitudinally plicate, rising from a small hypothallus. Capillitium of slender tubules, forming a dense net-work, bearing numerous rather small irregular nodules of lime, yellow or sometimes white in color, and often confluent along the axis of the sporangium. Spores globose, very minutely warted, dark violaceous, 8–10 mic. in diameter.

Growing on old leaves, sticks, herbaceous stems, etc. Sporangium and stipe .7–1.0 mm. in height and .3-.5 mm. in diameter, the stipe .2-.4 mm. long. The elongated form is the common one in this region. Craterium mutabile Fr.

b. Stipe longer than the sporangium.

7. Craterium nodulosum C. & B. Sporangium globose or obovoid, stipitate; the greater part of the wall a thin hyaline membrane, easily breaking away, covered externally with large white scales and nodules of lime; the basal portion naked, thickened, and more persistent, red-brown and plicate. Stipe long, erect or inclined, plicate, red-brown, rising from a small hypothallus. Capillitium of tubules forming a loose net-work, containing a variable quantity of lime in the shape of long irregular white nodules, sometimes confluent, with pointed lobes and branchlets. Spores globose, very minutely warted, dark violaceous, 10–12 mic. in diameter.

Growing on old wood, bark, leaves, etc. Sporangium .5-.6 mm. in diameter, the stipe two or three times as long. It is Badhamia nodulosa C. & B., Journal of Mycology, Vol. V, p. 186. Ravenel's specimens are on Acacia bark. Mr. Webber sent me elegant specimens from Florida where, he says, it grows commonly on the leaves and bark of the orange trees.

8. Craterium maydis Morgan, n. sp. Sporangium globose or obovoid, stipitate; the upper part of the wall a yellowish membrane, thin and fragile, covered with large thick scales and nodules of lime, amber-colored to golden-yellow; the basal portion thicker and more persistent, naked and plicate, red-brown. Stipe red-brown, long, slender, plicate, rising from a small hypothallus. Capillitium of thick tubules, forming a net-work with wide expansions at the angles; the nodules of lime large, numerous, yellow, angularly lobed and branched. Spores globose, very minutely warted, pale violaceous, 9–10 mic. in diameter.

Growing on old stalks of Zea mays. Sporangium with the stipe 1–1.5 mm. in height and .4-.6 mm. in diameter, the stipe always longer than the sporangium. I find it in abundance on old stalks of Indian corn, but never on anything else. See Plate XIV. Fig. 57.

VII. PHYSARUM Pers. Sporangium globose, depressed globose or irregular, stipitate or sessile; the wall a thin membrane, with an outer layer of minute roundish granules of lime, irregularly dehiscent. Stipe present or often wanting, never prolonged within the sporangium as a columella. Capillitium of slender tubules, forming an intricate net-work, the extremities attached on all sides to the wall of the sporangium; the tubules more or less expanded at the angles of the net-work, and containing at varying intervals nodules of lime. Spores globose, violaceous.

Physarum is the central genus of the PhysaraceÆ from which all the others are detached by characters which for the most part are unimportant.

§1. Lapidium. Lime in the Capillitium scanty; the nodules small, roundish, ellipsoidal or fusiform.

A. Sporangium stipitate.

a. Sporangia regular.

1. Physarum nutans Pers. Sporangium orbicular, very much depressed, the base concave or umbilicate, stipitate, cernuous; the wall a thin pellucid membrane, thickly covered with minute white or yellow roundish scales of lime, breaking up into irregular fragments, which often remain attached to the capillitium. Stipe long, slender, tapering upward, bent or curved at the apex, longitudinally rugulose, brown or blackish at the base, becoming paler upward and cinereous or whitish at the apex. Capillitium of very slender threads, rising from the base of the sporangium, forming a net-work with much elongated meshes, scarcely expanded at the angles; the nodules of lime white or yellow, ellipsoidal or fusiform, often very small and few in number, sometimes rather large and numerous. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on wood, bark, mosses, etc. A very common species. Sporangium .4-.5 mm. in diameter, the stipe 1–2 mm. in length, the lime-nodules commonly not thicker than the spores, but sometimes from once to twice their diameter. Under this name I have included all the lenticular species of Persoon's Synopsis, Physarum nutans, P. luteum, P. viride and P. aureum. There is no difference in these species, except in the color of the granules of lime; the form of the sporangium and the shape and color of the stipe are the same in all of them. No two authorities agree in the presentation of this species.

2. Physarum cupripes B. & R. Sporangium orbicular, much depressed, the base umbilicate, stipitate, cernuous; the greater part of the wall thin and delicate, with a scanty covering of yellow granules of lime, becoming naked and then brassy and iridescent, after maturity soon disappearing; the lower basal portion thicker and more persistent, with a layer of small yellow scales of lime. Stipe long, flexuous, bent at the apex, plicate, pale brown to yellow-brown, darker toward the base. Capillitium of slender tubules, forming a dense persistent net-work, more or less expanded at the angles; the lime-nodules small, numerous, yellow, angular and fusiform, below often confluent. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old wood; rare. Sporangium .4-.5 mm. in diameter, the stipe two or three times this length. The lime nodules are found both on the sides and at the angles of the meshes, and are fusiform or angular accordingly; the lime is scanty above, but in the lower part of the capillitium the nodules sometimes run together into lobed and branched forms. This is Physarum berkeleyi of Rostafinski's monograph.

3. Physarum obrusseum, B. &. C. Sporangium globose, the base usually slightly flattened or umbilicate, stipitate and cernuous; the wall a thin, violaceous membrane, covered by small, roundish, white or yellow scales of lime, or sometimes naked, splitting irregularly from the apex downward. Stipe long, slender, tapering upward, flexuous, bent or curved at the apex, yellow, yellow-brown, or pale brown. Capillitium of very slender tubules, forming a loose net-work, scarcely expanded at the angles; the nodules of lime small, white or yellow, roundish or obtusely angular, few to numerous, rarely wanting. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old wood, bark, mosses, etc Sporangium .2-.4 mm. in diameter, the stipe 1–2 mm. in length, the lime nodules when abundant once to twice the diameter of the spores, when scanty very small. This, as I find it growing, is an extremely variable species; I think its various forms and appearances cover such species as Didymium obrusseum B. & C.; D. tenerrimum B. & C.; Physarum tenerum Rex, etc., etc. See Plate XIV. Fig. 58.

4. Physarum nucleatum Rex. Sporangium globose, stipitate, erect or slightly nodding; the wall a thin, pellucid membrane, thickly covered with minute, white, roundish scales of lime, which are exceptionally sparse or absent, rupturing irregularly. Stipe long, slender, yellowish-white, longitudinally rugulose, tapering upward, expanded at the base into a small hypothallus. Capillitium of very slender tubules, forming a delicate net-work of small meshes, scarcely expanded at the angles; nodules of lime small, not numerous, roundish, white, usually concentrated into a large lump in the center of the sporangium. Spores globose, very minutely warted, violaceous, 6–7 mic. in diameter.

Growing on old wood, bark, etc.; rare. Sporangium .4-.5 mm. in diameter, the stipe two or three times as long, the lime-nodules about the size of the spores. The species much resembles some of the forms of P. obrusseum, but is to be distinguished by its central mass of lime and the small spores.

5. Physarum compactum Wingate. Sporangium depressed-globose, the base slightly umbilicate, stipitate, cernuous; the wall a thin, violaceous membrane, rugulose and iridescent, studded with large and thick, snow-white, roundish or elliptic scales of lime, at maturity splitting from the apex downward into several segments. Stipe long, rather weak, bent and flexuous, tapering upward, longitudinally rugulose, from snow-white to whitish-ochre and smoky-white, usually brownish at the base, and arising from a thin hypothallus. Capillitium a delicate net-work of very slender threads, with no expansions at the angles; the lime mostly concentrated in one large, snow-white nodule at the center, a few very small, roundish nodules scattered through the net-work. Spores globose, very minutely warted, violaceous, 7–9 mic. in diameter.

Growing on old wood, mosses, etc.; a common species. Sporangium .4-.5 mm. in diameter, the stipe two or three times this length. Tilmadoche compacta Wingate. It is doubtful if Tilmadoche columbina Rost. belongs to this species. According to Lister, Lepidoderma stellatum Massee, is the same as this species, and if it be objected to the name that there is already a Physarum compactum Ehrenberg, it may have to be called Physarum stellatum.

b. Sporangium more or less irregular.

6. Physarum leucophÆum Fr. Sporangium globose or depressed-globose, more or less irregular, the base never umbilicate, stipitate or subsessile; the wall a thin violaceous membrane, rugulose and iridescent, with a thin coat of small white scales and granules of lime, or sometimes nearly naked. Stipe variable in length, sometimes very short or quite obsolete, occasionally a few of them confluent, wrinkled, and sulcate, brown below, paler or whitish above. Capillitium a dense irregular net-work of slender tubules, more or less expanded at the angles; the nodules of lime white, small, roundish, or angular, few and scattered. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old wood, bark, leaves, etc. The sporangium .5-.7 mm. in diameter, the stipe about the same length, or shorter, and sometimes wanting. The lime on the wall and in the capillitium is never abundant and sometimes extremely scanty. Rostafinski's presentation of this species applies well to our specimens.

7. Physarum connexum Link. Sporangia subglobose, depressed, more or less irregular, sometimes confluent, stipitate, or subsessile; the wall a thin violaceous, or brownish membrane, rugulose, thickly covered with small white roundish scales of lime, which sometimes accumulate so as to make the surface rough and uneven. Stipe short, thick, rugulose, from snow white to smoky or sooty, especially toward the base, sometimes with a scanty calcareous hypothallus. Capillitium a loose net-work of tubules, much expanded at the angles; the nodules of lime small, white, rather numerous, ellipsoidal or fusiform, sometimes confluent and elongated. Spores irregularly globose, minutely warted, dark violaceous, 9–11 mic. in diameter.

Growing on old wood and bark. Sporangium .6–1.0 mm. in diameter, the stipe usually shorter than the diameter, sometimes very short; the lime-nodules about the thickness of the spores. This is a larger and rougher species than P. leucophÆum, the sporangium is more often irregular and the spores darker colored. P. confluens and P. connexum of Link. See Plate XIV. Fig. 59.

8. Physarum compressum A. & S. Sporangium laterally compressed and much flattened, subreniform, stipitate or subsessile; the wall a thin violaceous or brownish membrane, rugulose, thickly covered with small white roundish nodules of lime, similar to those in the capillitium. Stipe short, brown or blackish at least below, sometimes pallid or grayish above, longitudinally rugulose. Capillitium of slender tubules, forming a loose net-work; the nodules of lime small, white, very numerous, roundish or ellipsoidal, often confluent end to end. Spores irregularly globose or angular, minutely warted, dark violaceous, 11–14 mic. in diameter.

Growing on old stalks and leaves of Zea mays. Sporangium variable, .6–1.0 mm. in breadth, the stipe 1 mm. or less in length; the lime nodules about the thickness of the spores. According to Saccardo this species is the same as Physarum nephroedium Rost.

9. Physarum polycephalum Schw. Sporangia confluent into a subspheric gyrose-complicate head, composed of several to many laterally compressed, irregular, simple sporangia; the wall a thin, pellucid membrane, covered by a thin layer of minute scales of lime, white to yellow or greenish-yellow Stripes thin, flat, weak, and often prostrate, pale yellow, more or less connate, arising from a thin hypothallus. Capillitium of slender tubules forming a loose, irregular network, more or less expanded at the angles: the lime-nodules white or yellow, small, fusiform or by confluence elongated and sometimes branched. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old bark, wood, leaves, etc. The sporangia rarely simple, usually confluent into a head of from four or five to fifteen or twenty, and sometimes more, simple sporangia; the stipes variable in length, long or short, rarely wanting. The gray form is Didymium polymorphum Mont., the yellow-green form D. gyrocephalum Mont. Sprengel considered this species the same as Physarum compactum Ehr., and it appears under this name in Schweinitz's North American Fungi; but Fries, who had seen specimens of both, disposed of them differently. See Plate XIV. Fig. 60.

10. Physarum didermoides Pers. Sporangia obovoid-oblong, stipitate, growing close together on a white membranaceous common hypothallus; the wall with a thick, white, outer layer of lime, easily crumbling and falling away, leaving the sporangium dark gray; the inner membrane rather thick and firm, violaceous, with a closely adherent layer of granules of lime. Stipes very short, white, thin, and weak, each formed by a bit of membrane arising from the hypothallus. Capillitium a loose net-work of slender threads, bearing numerous roundish or irregular white nodules of lime. Spores irregularly or angularly globose, minutely warted, dark violaceous, 12–15 mic. in diameter.

Growing on wood, leaves, grass, etc. Sporangia .6–1.2 mm. in length by .4-.6 mm. in thickness, the stipe shorter than the sporangia. Spumaria licheniformis Schw., belongs here. This is a truly abnormal species of Physarum, so much so that Fries, in the Summa Veg. Scand. placed it by itself in a separate genus, Claustria.

B. Sporangia sessile.

11. Physarum confluens Pers. Plasmodiocarp roundish, oblong or elongated, and by confluence branched and reticulate; the wall a thin, violaceous membrane, rugulose, with a thin, closely adherent layer of minute granules of lime, over which are scattered small, white, roundish nodules, which sometimes accumulate into a thick, pulverulent coat. Capillitium a loose net-work of tubules, widely expanded at the angles; the nodules of lime small, white, very numerous, roundish or ellipsoidal, by confluence elongated and irregular. Spores irregularly globose, minutely warted, dark violaceous, 9–11 mic. in diameter.

Growing on old wood, bark, leaves, etc. Plasmodiocarp .4-.5 mm. in thickness, varying from roundish to much elongated, creeping and reticulate. The sporangium before dehiscence is gray, whence Link's name, Physarum griseum; the loose pulverulent coating of lime easily falls away, leaving the sporangium dark colored, whence Rostafinski's name, Physarum lividum. The amount of lime on the wall and in the capillitium is variable.

12. Physarum luteolum Peck. Sporangia small, subglobose, sessile, closely gregarious; the wall a thin membrane, covered by a layer of small scales of lime, yellowish, inclining to tawny, in color, rupturing irregularly. Capillitium of slender tubules, forming a dense net-work of small meshes, scarcely expanded at the angles; the nodules of lime small, numerous, yellowish, roundish, or ellipsoidal. Spores globose, nearly smooth, violaceous, about 10 mic. in diameter.

Growing on living leaves of Cornus canadensis, Adirondack Mountains, New York. I have not seen a specimen of this Physarum, but from Professor Peck's description and figure it seems to be a unique species.

13. Physarum thejoteum Fr. Sporangia very small, sessile, on a thin membranaceous hypothallus, closely crowded together and more or less connate, subobovoid or oblong, irregular from mutual pressure; the wall a thin violaceous membrane, closely covered with a thin layer of small irregular scales of lime, tawny or yellowish tawny in color, breaking up irregularly about the apex. Capillitium a loose irregular net-work of slender threads, more or less expanded at the angles; the lime nodules small, tawny or yellowish, not numerous, ellipsoidal or fusiform, by confluence elongated and irregular. Spores globose, even, violaceous, 6–7 mic. in diameter.

Growing on old wood, mosses, etc. Sporangia .2-.4 mm. in diameter at the apex, densely packed and their walls grown together, approaching the aethalioid structure; the lime-nodules from one to two or three times the diameter of the spores in thickness. I have described my specimens, which are abundant, very carefully, and judge them to be referable to this species; if so, they show that the species should be kept apart from Physarum virescens. Didymium nectriÆforme B. & C., is evidently this same species.

14. Physarum lateritium B. & R. Sporangia sessile, irregularly globose and gregarious, or by confluence more or less elongated and plasmodiocarp; the wall a thin violaceous membrane, rugulose and iridescent, closely covered with small irregular scales of lime, from testaceous or brick-red to bright red in color. Capillitium a dense irregular net-work of tubules, much expanded at the angles; the nodules of lime small, very numerous, roundish or angular, whitish or yellowish, sometimes tinged with red granules. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old wood, sticks, leaves, etc. Sporangia .4-.6 mm. in diameter, by confluence sometimes much elongated; the lime-nodules two or three times the diameter of the spores in thickness. Didymium lateritium B. & R. Physarum inequale Peck, is the same species. See Plate XIV. Fig. 61.

§2. Saxella. Lime in the capillitium abundant, the nodules large, angular or irregular, with pointed lobes and branchlets.

A. Sporangia stipitate.

15. Physarum imitans Racib. Sporangium depressed-globose, the base flattened or umbilicate, stipitate, erect or cernuous; the wall a thin violaceous membrane, with a closely adherent layer of minute granules, over which are scattered rather large, roundish or irregular white scales of lime, splitting from the apex downward into a few irregular segments. Stipe short, thick at the base and tapering upward, longitudinally rugulose, from gray to brown or blackish, especially below. Capillitium a loose irregular network of tubules, widely expanded at the angles; the nodules of lime white, numerous, large, irregular, with pointed angles and lobes. Spores globose, very minutely warted, violaceous, 8–9 mic. in diameter.

Growing on old wood, mosses, etc. Sporangium .4-.5 mm. in diameter, the stipe about the same length or a little longer. The species superficially resembles the gray form of Physarum nutans, and quite likely is constantly overlooked on this account. Although I am not able to verify my reference, yet my specimens answer so well to the description of Raciborski that I am unwilling to invent a new name. See Plate XIV. Fig. 62.

16. Physarum ornatum Peck. Sporangium globose or depressed-globose, stipitate; the wall a thin yellowish membrane, covered with minute granules and small irregular scales of lime, yellow to orange in color. Stipe short, erect, blackish-brown, black at the base, longitudinally plicate, rising from a small hypothallus. Capillitium of tubules forming a rather dense net-work, with wide expansions at the angles; the nodules of lime large, numerous, yellow, irregular, sometimes confluently branched and reticulate. Spores globose, minutely warted, dark violaceous, 10–12 mic. in diameter.

Growing on old wood, bark, mosses, etc. Sporangium about .5 mm. in diameter, the stipe about the same length or shorter. Physarum oblatum McBride, can not be distinguished from this. Specimens of this species in the herbarium of Schweinitz are labeled Physarum sulphureum; this is without doubt a mistake.

17. Physarum gravidum Morgan, n. sp. Sporangium depressed-globose, the base umbilicate, stipitate; the wall a thin, violaceous membrane, brownish at the base, with a thin coat of small, white scales and minute granules of lime. Stipe long, erect, brown or reddish-brown, darker below, tapering upward, expanding at the base into a small hypothallus. Capillitium of slender tubules forming a loose net-work, more or less expanded at the angles and for the most part filled with lime; the nodules white, slender, much elongated and branched, with pointed lobes and branchlets. Spores globose, very minutely warted, dark violaceous, 11–13 mic. in diameter.

Growing on old stalks of Zea mays. Sporangium .5-.6 mm. in diameter, the stipe about twice this length. The lower part of the capillitium is sometimes entirely filled with lime, so that the species approaches Badhamia in the structure of its capillitium.

18. Physarum leucopus Link. Sporangium globose, the base slightly flattened, stipitate; the wall a thin, violaceous membrane, with a white, pulverulent outer coat of minute granules of lime. Stipe short, thick, erect, snow-white, longitudinally rugulose, tapering upward, expanding at the base into small, white hypothallus. Capillitium a loose net-work of tubules, with wide expansions at the angles; the nodules of lime large, white, numerous, irregularly lobed and branched. Spores globose, very minutely warted, violaceous, 8–10 mic. in diameter.

Growing on old wood, leaves, etc. Sporangium .3-.4 mm. in diameter, the stipe about the same length as the diameter. Our specimens are a smaller form than the European, with smaller and smoother spores. Superficially the species resembles Didymium squamulosum, and it is Didymium leucopus of Fries, S. M.

19. Physarum glaucum Phillips. Sporangium globose, or the base slightly depressed, stipitate; the wall a thin, violaceous membrane, covered with minute, white granules and small roundish or irregular scales of lime. Stipe short, stout, erect, black, longitudinally wrinkled, expanding at the base into a small hypothallus. Capillitium of much-flattened tubules, forming a loose net-work, widely expanded at the angles; the nodules of lime numerous, large, white, irregular, with pointed angles and lobes. Spores globose, very minutely warted, dark violaceous, 12–14 mic. in diameter.

Growing on old leaves: California. Sporangium .5-.7 mm. in diameter, the stipe not longer than the diameter. This is quite a robust species, both externally and in the broad, flat tubules of the capillitium. See Plate XV. Fig. 64.

20. Physarum relatum Morgan, n. sp. Sporangium globose, the base umbilicate, stipitate, often cernuous; the wall a thin, violaceous membrane, rugulose and iridescent, covered with small, roundish or irregular white scales of lime. Stipe long, erect or inclined, rising from a thin hypothallus, tapering upward, white or cream color to ochraceous. Capillitium a dense net-work of tubules, more or less expanded at the angles, and almost entirely filled with white granules of lime, leaving only here and there short, slender empty spaces. Spores globose, nearly smooth, violaceous, 8–9 mic. in diameter.

Growing on old wood. Sporangium .5-.6 mm. in diameter, the stipe about twice this length. The capillitium is rigid, with the abundance of lime almost as in the genus Badhamia. Superficially the species much resembles Cytidium globuliferum or Physarum compactum, but the disposition of the lime on the wall and in the capillitium is altogether different. See Plate XIV. Fig. 63.

21. Physarum auriscalpium Cke. Sporangia subglobose, depressed, substipitate; the wall a hyaline membrane with a thin, closely adherent layer of minute granules of lime, over which are scattered large, irregular, orange-red scales of lime. Stipe very short, sometimes almost obsolete. Capillitium of tubules forming a loose net-work, with widely expanded angles, and mostly filled with orange granules of lime, only here and there short, slender, empty spaces. Spores globose, minutely warted, dark violaceous, 11–13 mic. in diameter.

Growing on rotten wood; South Carolina, Ravenel. Sporangia .6-.8 mm. in diameter, the stipe very short. Described in Annals of the Lyceum of Natural History of New York, June, 1877. So fine a species ought to be found again. Cooke's specimen was examined by Lister, Mycetozoa, p. 61.

EXPLANATION OF PLATE XIV.

• Fig. 56.—Craterium minimum B. & C. a. Sporangia × 5. b. Sporangium with lid × 90. c. Capillitium and spores × 500.
• Fig. 57.—Craterium maydis Morgan. a. Sporangia × 5. b. Sporangium × 90. c. Capillitium and spores × 500.
• Fig. 58.—Physarum obrusseum B. & C. a. Sporangia × 5. b. Sporangium × 90. c. Capillitium and spores × 500.
• Fig. 59.—Physarum connexum Link. a. Sporangia × 5. b. Sporangium × 90. c. Capillitium and spores × 500.
• Fig. 60.—Physarum polycephalum Schw. a. Sporangia × 5. b. Sporangia × 90. c. Capillitium and spores × 500.
• Fig. 61.—Physarum lateritium B. & C. a. Sporangia × 5. b. Sporangia × 90. c. Capillitium and spores × 500.
• Fig. 62.—Physarum imitans Racib. a. Sporangia × 5. b. Sporangium × 90. c. Capillitium and spores × 500.
• Fig. 63.—Physarum relatum Morgan. a. Sporangia × 5. b. Sporangia × 90. One divested of the wall and showing the rigid capillitium. c. Capillitium and spores × 500.

The Journal of the Cin. Soc. Natural History
Vol. XIX. Plate XIV.
Morgan on Myxomycetes.