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 µ.
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 extremebase 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 suggestTilmadoche viride, but the entire habit precludes such reference. Perhaps nearest toP. melleum.
Castillo, Nicaragua.
Miss Lister thinks this the same asP. tenerumRex. 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, 1a, 1b, 1c.
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-likehypothallus; 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 µ.
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 theouterperidium 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'sCrateriachea; that is, the lime is massed as a snow-white pseudo-columellain 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 µ; not infrequently a single spore reaches 16 µ, 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 ofPopulusandNegundo.
Brazil, India, Japan.
Physarum lividumRost.,Mon., p. 95, is but a less calcareous form of this, as is evident even by the author's description. Professor Morgan thoughtP. lividuma phase ofP. griseumLk. Link, however, reckonsP. griseumthe same asP. cinereum. Link,Diss., I., p. 27.
37.Physarum leucopusLink.
Plate IX., Figs. 7, 7a, 7b.
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 µ.
The snow-white, nearly smooth stem, the small sporangium (½ mm.) covered with loose calcareous granules, distinguish this rare species. It looks like a smallDidymium squamulosum. Fries called itD. leucopus,Syst. Myc., III., p. 121.
Rare. Iowa, Ohio, Maine; Portugal.
38.Physarum compressumAlb. & Schw.
Plate XVIII., Fig. 14, andPlate XIX., Fig. 12 and Fig. 4.
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 µ.
P. affineR. was in this connection set up for European types compressed indeed, but more stronglyreniform. The author says in his further description that the formaffineis 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. affineRost.,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 notabilenom. nov.
Plate IX., Figs. 2, 2a, 2b;Plate XV., Fig. 2; andFrontispiece.
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 µ.
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. nefroideumof Strasburg herbarium turns out, after all,testeLister, to beP. compressumAlb. & Schw., which accordingly shall now enjoystate 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'sDidymium connatum, which indeed represents the present species. In such disposition, how gladly would all concur, were the thing possible! ButPhysarum connatumis already a synonym twice over.[25]Unless we are done with the rules entirely,P. connatumcannot stand.P. polymorphumandP. leucophaeumare 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 tropicaleMacbr.
Plate XV., Figs. 4, 4a, 4b.
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 µ.
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 suggestCraterium, but the internal structure is not at allCraterium-like. The capillitium is typically ofPhysarum. The color suggestsP. leucophaeum violascensRost. 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 nicaraguenseMacbr.
Plate XV., Figs. 7, 7a, 7b;XVII., 11 and 11a.
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 µ 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 fromP. notabilein 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 resemblingP. polycephalum. Besides, the sporangia are uniformly much smaller, and show constantly the strongly calcified centre, much transcending anything seen inP. 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 withP. leucophaeum.
In theMycetozoa, 2nd ed., l. c., the present species is entered as a synonym of two described by Massee:Tilmadoche reniformisMass., Mon., p. 336, andDidymium echinosporumMass.,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 umbilicatebelow, sausage-shaped and curved; the stem elongated slender erect, pale brown;capillitial nodes scattered, fusiform, colorless or yellow; spores 16–17 µ." It is evident that whatever Massee may have had in hand as he wrote it wasnot P. nicaraguense, which has spores 10–12µand reverses the remaining description.
ButDidymium echinosporumalso definesT. reniformissince Lister,Mon., p. 54, says they are based on two gatherings of one species. Of this second species Massee says: "A superficial resemblance toT. nutans, but distinct in the capillitium which containsno trace of lime; spores 12–14 µ!" Again it is evident that whatever Massee had in hand when he wrote, it was notP. nicaraguensewhich "has capillitium almost Badhamia-like," i. e., burdened with lime!
Worse than all; Mr. Massee'sallegedtypes are in evidence; one labelledP. reniforme[26]includes forms ofP. didermoidesand ofP. nicaraguense; the other labelled by BerkeleyP. nutansisP. 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 sulphureumAlb. & Schw.
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 µ.
Northern Europe. (Lusatia) Lausitz, Alb. & Schw.; dim oldWendish 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 inMyxomycetes of the U. S.It surely will be found again. Mr. Lister thinksP. variableRex may be the same thing.
43.Physarum carneumG. Lister and Sturgis.
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 µ.
Differs fromP. citrinellumin the membranous peridium, flesh-colored stalks and smaller spores.
Colorado;Dr. W. C. Sturgis.
44.Physarum citrinellumPeck.
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 imperfectlydefined 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 µ.
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 theTwenty-second N. Y. Report, Dr. Peck incorrectly referred this species toPhysarum citrinumSchum. On the appearance of Rostafinski'sMonograph, Dr. Peck in his revised list,l. c., writesP. citrinellumPeck, 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 toP. caespitosumSchw., of which the original description is as follows: "P. caespitosumL. 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 albescensEllis.
Plate XVI., Figs. 4, 4a.
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 µ. Varies to forms with single (inner) peridium and simple physaroid capillitium.Vid.descriptions cited forP. 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 genusLeocarpus; 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 toDiderma albescensPhillips, (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 theMyxomycetes of East. Iowa, referred his part of this Iowa gatheringto thePhysarum auriscalpiumCke. 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 ofP. virescensDitmar,P. nitensList.
Meantime in 1898 Colorado material from Professor Bethel reached the University. This did not recall any of the materials sent from Ellis.Diderma albescenshad meanwhile come again from California, and been recognized asDiderma niveumRost.
Accordingly, inN. 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 monotypicLeocarpus, 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 thatit 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 representsP. nitens, physaroid, single-walled; while the Philadelphia part of the gathering corresponds, poorly it is true, but in fact, asnowappears, to the form coming in perfection from Colorado; leocarpine in structure, published asLeocarpus fulvus;P. fulvumLister. Since the combinationP. fulvumis already in use, synonym ofP. rubiginosum, it seems better to write the name suggested by Ellis;Physarum albescensnever having been published, becauseDiderma albescens, as noted took care of itself.
Since Rostafinski we separate all these physaroid forms chiefly by capillitial characters: capillitial structure separates genera.Physarum didermais a physarum despite its double wall. And so hereLeocarpuswas 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 inPhysarum, but in large masses involve portions of the net itself, nodes and all, as inLeocarpus. Miss Lister's beautiful figures,op. cit., Figs. 66 and 82, show this very well.
In TheJournal 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 toLeocarpus fragilisRost., 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 ofP. (L.) fulvumare membranous and rugose with included deposits of lime granules and show nothing of the polished cartilaginous layers characteristic ofL. 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 writesPhysarum, and believes the question of identity in a perplexing case fortunately settled.
46.Physarum variabileRex.
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 µ.
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 auriscalpiumCooke.
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 µ in diameter, brownish-violet by transmitted light, black in the mass.
This is the original description, 1893, ofP. sulphureum(Alb. & Schw.) Sturgis; the author last named having compared certain stalked New England forms with what he could find ofP. sulphureumin the herbarium of Schweinitz at Philadelphia, and having, as he thought, established identity.
Meantime Mr. Lister had been inclined to referP. auriscalpiumCke. toP. rubiginosumFr.,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 labelledP. auriscalpiumCke.
AccordinglyP. sulphureumis 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. MeanwhileP. sulphureumSturgis stands, a new type forP. auriscalpiumCke., 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 oblatumMacbr.
Plate III., Fig. 6;Plate XIV., Figs. 3, 3a, 3b.
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 µ.
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 asCraterium maydis. But it is doubtless a physarum, occurring on habitats of all sorts, from Ohio to Iowa, Colorado and Washington. Ceylon(?).
Physarum ornatumPeck is doubtfully cited here, although Professor Morgan thought it the same asP. oblatum. As a matter of fact the original brief description,op. cit., does not suggest eitherP. oblatumorP. maydis; rather a form ofTilmadoche viridis. ProfessorSturgis,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 nameP. ornatumPk. "should be discarded."
49.Physarum galbeumWing.
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 µ.
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 tenerumRex.
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 µ.
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 asP. obrusseumfollowing the Polish text. Miss Lister who has the type ofDidymium obrusseumat hand considers it as representing a phase ofPhysarum polycephalumSchw.D. tenerrimumBerk. & Curt. is judged the same.P. tenerumRex is, in any event, certain, and the combination is adopted.
Rare:—Pennsylvania, Ohio, Louisiana, Texas, Iowa, Portugal, Japan.
51.Physarum flavicomumBerk.
Plate XV., Figs. 3, 3a.
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 µ.
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 ofTilmadoche. Indeed, the present species unites characters supposed to distinguishPhysarumfromTilmadoche, 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 fromP. 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.
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 µ.
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.
SECTION 2
TilmadocheFries
53.Physarum gyrosum(Rost.)Jahn.
Sporangia gyrose, variable in form, or plasmodiocarpous and irregular, venulose, sessile upon a common, strongly developed hypothallus, sometimes isolated and irregularly globose, dehiscing irregularly or by longitudinal fissure, yellowish or greyish white; columella none; capillitium delicate, the nodules elongate, variable in size; spores pale violaceous, minutely spinulose, 7–10 µ.
This is a European species recently resuscitated by Dr. Jahn. It perhaps might more correctly be recorded asP. gyrosumJahn, since Rostafinski certainly attempted in his description to cover two apparently distinct things. He seems to have had before himFuligo muscorumSchw. and "P. gyrosum," but he thought them the same, and his description touches now one, now the other. SinceF. muscorumSchw. has all along held its own and received due recognition, it is interesting to note the recovery of this gyrose form.
Judging by description and figures, it resembles a very large, sessile phase ofP. polycephalum. See further under that species.
Europe, Japan, Eastern United States (?).
54.Physarum polycephalumSchw.
Plate VIII., Figs. 2, 2a, 2b.
Sporangia spherical or irregular, impressed, gyrose-confluent, helvelloid, umbilicate below; peridium thin, ashy, covered with evanescent yellow squamules, fragile; stipe from an expanded membranaceous base, long-subulate, yellow; spores smooth, violet, 9–11 µ.
A most singular species and well defined is this, occurring in masses of decaying leaves or on rotten logs. The plasmodium at first colorless; as it emerges for fructification, white, then yellow, spreading far over all adjacent objects, not sparing the leaves and flowers of living plants; at evening slime, spreading, streaming, changing; by morning fruit, a thousand stalked sporangia with their strangely convoluted sculpture. The evening winds again bear off the sooty spores, and naught remains but twisted yellow stems crowned with a pencil of tufted silken hairs. August.
Although Rostafinski's description of this species is accurate and marks exactly aTilmadocheand is very different from his description ofPhysarum polymorphum, nevertheless it is probable that both descriptions have reference to the same thing. All specimens on which both species were based were American;P. polymorphum, North American. But the only North American form to which reference can be made is that by Schweinitz calledP. polycephalumand, fortunately, sufficiently described. Furthermore, Rostafinski, underT. gyrocephala, himself affirms the probable identity of Montagne'sDidymium gyrocephalumwith the Schweinitzian species, and uses Montagne's specific name provisionally. For these reasons it seems proper to write the species as above.
Widely distributed and common, from Maine and Canada to Nebraska, and Washington and south to Nicaragua.
This species is so common that its plasmodium and fructification may be easily observed. Professor Morton E. Peck, who has been for years a close observer of the vegetative phases of our Iowa species, says ofP. polycephalum: "In one instance I observed a plasmodium for twelve successive days on the surface of a decaying stump. During this period it crept all around the stump and from top to bottom several times. At one time the color was bright yellow; at another, greenish yellow; and once, shortly before fruiting, it became clear bright green. A heavy rain fell upon the plasmodium but it appearedto sustain little injury and ultimately developed normal sporangia."
55.Physarum nutansPers.
Sporangia gregarious, depressed-spherical, stipitate, umbilicate, gray or white, thin-walled, nodding; stipe long, tapering upward, brown or black below, ashen white above, lightly striate, graceful; capillitium abundant, threads delicate, intricately combined in loose persistent network with occasional minute, rounded, or elongate calcareous nodules; spores minutely roughened, globose, about 10 µ.
The nodding, lenticular, umbilicate sporangium, barely attached to the apiculate stipe, is sufficient to distinguish this elegant little species, recognized and quite aptly characterized by mycologists for more than one hundred years. AsSphaerocarpus albusBulliard first prescribed the limits by which the species is at present bounded. The description by Fries (Syst. Myc.,, III., 128) is especially graphic; "Peridium very thin, in form quite constantly lenticular, umbilicate at base, at first smooth then uneven, generally laciniate-dehiscent, the segments persistent at least at base."
The stipe is usually white above, fuscous below, at the apex almost evanescent; hence the cernuous sporangia. The same character is less strikingly manifest in the species next following.
The plasmodium is bright yellow, sometimes greenish. Brought in from the field and maturing under a bell-jar, the color changes to a watery white just before the sporangia rise in fruit.P. albumFuckel,Rhen. Fl., No. 1469, 1865, is believed to beP. cinereum(Batsch) Pers.
Persoon changed Bulliard's specific name in this case to furnish one himself, more descriptive as he thought and distinctive. His success in this attempt must be esteemed but partial since all the related forms, immediately listed,nodas well. Bulliard's name as applied by Persoon is therefore to be preferred. But the transfer fromTilmadochetoPhysarumloses for us one step in the ladder of priority.P. album(Bull.) may not enter here, since Fries has given us one species under that title. So Persoon comes next on the list, all the world now nodding approbation, let us hope!
Under the namePhysarum gracilentum, Fries cites an extremely delicate form of this species. The sporangia are of the most minute, about .2–.3 mm. in diameter, globose, slightly umbilicate below, the stipe usually white at top, but sometimes black throughout. This graceful form occurs rarely in undisturbed woods.
Widely distributed in the eastern United States, apparently rare in the west. Reported from various parts of the world; Europe, Japan, Australia, etc.
56.Physarum viride(Bull.)Pers.
Plate VIII., Fig. 8, 8a, 8b.
Sporangia globose, flattened or lenticular, beneath plane or concave, variously colored, yellow, greenish yellow, rusty orange, stipitate, nodding; the peridium splitting irregularly or reticulately; stipe variable in length and color, through various shades of red and yellow, subulate; capillitium strongly developed, concolorous with sporangium, the tubes with colorless or yellow calcareous thickenings; spores smooth, fuscous or violet-black, 8 µ.
A very handsome and rather common little species; like the preceding, but generally greenish-yellow in color, and occasionally brilliantly orange without a suggestion of green. Indeed, the color is so variable that some authors have been disposed to discard the species entirely, inasmuch as the chief specific character is color. The plasmodium is pale yellow, in rotten logs, stumps, etc. In the paler yellow or greenish forms the stipe is more commonly black.
This isPhysarum luteum(Bull.) Fries, and likewise also includes the three varieties,viride,aureum,coccineum, listed by the same author underP. nutans, while he at the same time remarks that they might with equal propriety be elsewhere referred. Rostafinski considers that all the colored forms agree in capillitium sufficiently to be associated under one name and are in the same way unlikeT. nutans.[29]Rostafinski thinks to avoid confusion by suggesting a more fitting specific name,T. mutabilis, but there seems no good reason for not adopting the earliest identifiable specific appellation, which in this case appears to beviride. The yellow phase is common in Iowa, resembles in size, color, stipe,P. galbeumWingate, but is instantly distinguishable by the capillitium.N. A. F., 1213.
Widely distributed specimens are before us;—from New England, New York, Pennsylvania, Maryland, Ohio, Nebraska, Iowa, California, Oregon, Canada, Nicaragua, Samoa, Alaska, India, etc.
EXTRA-LIMITAL[30]
Physarum mutabile(Rost.)List.
Sporangia cylindrical ovoid or sub-globose white, plasmodiocarpous, sessile or stipitate, stipes when present yellow, with or without lime, often connected by a hypothallus; peridium thin, squamulose; capillitiumpersistent, intricate, the nodules white, more or less confluent at the center to form a real or a pseudo-columella; spores brownish-purple, spinulose, 7–8 µ.
Reported from Europe, Africa, Ceylon.
Physarum roseumBerk. & Br.
Plasmodium rose-red; sporangia gregarious, stipitate, globose, rose-red; the stipe erect, brown, rugulose, translucent; capillitium lax, delicate, lilac, the nodules few, large, purple-red, branching; spores reddish-lilac or brown, minutely spinulose, 7–10 µ.
Reported from Ceylon, Java, Borneo, Japan.
Physarum dictyospermumList.
"It is distinguished from the other known species ofPhysarumby the strongly reticulated spores. Its nearest ally is perhapsP. psittacinumwhich it resembles in having orange-red lime-knots and in the sporangium-wall being studded with orange crystalline disks."Lister.
Reported collected once only; New Zealand.
Physarum straminipesList.
Plasmodium white; sporangia greyish-white, obovoid or wedge-shaped, .7 mm. in diameter, clustered or scattered, stipitate or sessile, when stipitate stalks long, weak; peridium membranous, pale purple; capillitium a persistent rigid net, the nodules white, rounded, sometimes aggregate as a pseudo-columella; spores purple-brown, 10–11 µ, warted, the papillae in definite patches.
Related toP. compressum.
Reported from England; Germany.
Physarum crateriformePetch.
Sporangia gregarious, globose, clavate or crateriform, sessile orstipitate, white; stalk when present opaque conical, black below, white above, in crateriform sporangia entering and developed as a columella; capillitium various, strongly calcareous, the nodules either grouped in a pseudo-columella, or in globose sporangia, rod-like, ascending; spores closely spinulose, 11–15 µ.
Reported from Ceylon, Japan, West Indies; Lisbon.
Physarum gulielmæPenzig.
Plasmodium yellow; sporangia sub-globose, sessile, brownish-orange or chestnut brown, rugulose, clustered or heaped, often with a yellow membranous hypothallus; peridium membranous with clustered deposits of yellowish-brown lime granules; capillitium abundant, the nodes angular, branching, white; spores purplish brown, spinulose, 10–12 µ.
Reported from Java, Sweden, Switzerland.
Physarum echinosporumList.
This species is distinguished from the preceding chiefly in episporic characters. "Spores purple, 8 µ, marked by strong ridges and spines," 8 µ.
Reported from Antigua.
Physarum æneum(List.)R. E. Fries.
Sporangia sessile, sub-globose or plasmodiocarpous, pinkish-brown or bronze, glossy; peridium double, the outer somewhat cartilaginous, brittle, falling back from the shining, membranous inner wall; capillitium dense, the nodules not large, brown, sometimes aggregated to form a pseudo-columella; spores pale brownish-violet, nearly smooth, 6–8 µ.
Reported from West Indies, Bolivia.
Related Genus
TrichamphoraJunghuhn, p. 12.
Sporangia discoidal, above concave, saucer-shaped, stipitate; the capillitium variable, anon physaroid, badhamioid, or even as inDidymium.
This genus is set up for the accommodation thus far of the single species following. It differs fromPhysarellain the apparently constant discoidal shape, absence of trabecules, etc.
Trichamphora pezizoideaJungh.,op. cit.
Sporangia discoidal or saucer-shaped, gregarious, stipitate, erect or nodding, grayish-white, the peridium thin, breaking irregularly and persistent; stipe subulate, striate, reddish brown, transparent; capillitium variable as above stated; spores pale violet-brown, spinulose or nearly smooth, about 9 µ.
InMycetozoa, 2nd ed., the spores are described as "dark or pale purplish brown, spinose, spinulose or nearly smooth, 9–17 µ in diameter." This would seem too great a variation even in this protean species. The only specimens in our herbarium are from the Congo valley. The spores are pale and nearly smooth, as inTilmadoche alba, and 9 µ. Spores 17 µ suggest immaturity; penultimate cell-division.
The synonymy above cited shows how this species has impressed careful students. Doubtless in every case the reference is correct, judging from the specimen each author had before him, although it is hard to see howChondriodermamight have been suggested.
The species is evidently tropical, though reported from Europe.
4. CrateriumTrentepohl
Sporangia more or less distinctly cyathiform, stipitate, the peridium generally plainly of two layers or even of three, opening at the top by circumscission more or less definite, or by a distinct lid, the upper part calcareous often to a marked degree, the lower, cartilaginous, long persistent as a vasiform cup containing the capillitium and spores, the calcareous nodes aggregating more or less to form a pseudo-columella.
This genus is distinguished fromPhysarumandBadhamiachiefly by the form of the sporangia and the method of dehiscence. The capillitium is in some specimens particularly, of thePhysarumtype; in others, like that ofBadhamia. There are accordingly species that receive at the hands of different authors diverse generic reference as one feature or another in the structure is emphasized in the different cases. It is granted that it is hard to draw the line sometimes between forms in which the dehiscence is irregularly circumscissile and those in which the wall breaks without any regularity whatever, since, in all, the breaking up of the peridium usually begins at the top. Species here included will, however, offer little ambiguity.
Key to the Species of Craterium