Chapter X: Section 2: =Tilmadoche= Fries (3)

However, _A. speciosa_ Zuk. need not here concern us. Neither in his description nor figures does Zukal at all approach the form we study. His species is not an amaurochete; the size of the spores suggest that, to say nothing of the capillitial structure.

In the same volume VII., the distinguished author introduces another amaurochete, _A. minor_ Sacc. & Ellis, _Mich._ II., p. 566. This is American; sent from Utah by our famous pioneer collector Harkness. A specimen is before us: it is a lepidoderma! in shining, scaly armor dressed; vid. under _L. carestianum_.

Since the distribution of Washington material, as mentioned, our species reappears at various points in western Europe, points in England, etc., and will no doubt now share, hereafter as a century ago, the habitat so long conceded to the long familiar older type.

_B._ STEMONITACEAE

Capillitium abundant, springing usually as dissipating branches from all parts of the columella; the sporangia generally definite and distinct, though sometimes closely placed and generally rising from a common hypothallus.

=Key to the Genera of the Stemonitaceae=

_A._ Fructification aethalioid; capillitium charged
with vesicles 1. _Brefeldia_

_B._ Sporangia distinct, or nearly so.

_a._ Stipe and columella jet-black.

1. Capillitium so united as to form a surface
net 2. _Stemonitis_

2. Capillitial branch-tips free 3. _Comatricha_

_b._ Stipe and columella whitish; calcareous 4. _Diachaea_

=1. Brefeldia= _Rostafinski_

1873. _Brefeldia_ Rost., _Versuch_, p. 8.

Sporangia occupying in the aethalium several layers, those of the median, and especially of the lowest layers, furnished with columellae which blend beneath; capillitium threads in the lowest layers arising from the columella, in the upper extending radiately between the individual sporangia, and united at the sporangial limits by means of rather large inflated sacs.

The genus _Brefeldia_ is, like some others, difficult to dispose of in any scheme of classification where linear sequence must be followed. Rostafinski placed it in an order by itself. Its relationships are on the one hand with _Amaurochaete_ and _Reticularia_, and on the other with the _Stemonitales_, though easily distinguished from either. It is intermediate to _Amaurochaete_ and _Stemonitis_, and withal, as it appears to us, a little nearer the latter, as the limits of the individual sporangia are in _Brefeldia_ pretty well defined.

1. BREFELDIA MAXIMA (_Fr._) _Rost._

PLATE V., Figs. 7, 7 _a_, 7 _b_, and PLATES XXI., XXII.

1825. _Reticularia maxima_ Fries, _Syst. Orb. Veg._, I., p. 147.
1875. _Brefeldia maxima_ (Fr.) Rost., _Versuch._, p. 8.

Aethalium large, four to twenty cm, papillate above, violet-black at first, then purple or purple-brown, developed upon a widespread, silver-shining hypothallus; sporangia in favorable cases distinct, indicated above by the papillae; columellae obscure, black; capillitium abundant, the threads uniting by multifid ends to surround as with a net the peculiar vesicles; spore-mass dark violet-black, the individual spores paler by transmitted light, distinctly papillose, 12-15 mu.

A very remarkable species and one of the largest, rivalled by _Fuligo_ only. To be compared with _Reticularia_, which it resembles somewhat externally, and with some of the larger specimens of _Enteridium_. The plasmodium at first white with a bluish tinge is developed abundantly in rotten wood, preferably a large oak stump, and changes color as maturity comes on, much in the fashion of _Stemonitis splendens_, leaving a widespread hypothallic film to extend far around the perfected fruit-mass. In well-matured aethalia, "_Jove favente_," the sporangia stand out perfectly distinct, particularly above and around the margins. Closely and compactly crowded, they become prismatic by mutual pressure, and attain sometimes the height of half an inch or more. In the centre of the fructification, next the hypothallus, the sporangia are very imperfectly differentiated. Many are here horizontally placed, and perhaps supplied with an imperfectly formed peridium,--if so are to be interpreted the lowest parts of the capillitial structure, the long, branching, ribbon-like strands which lie along the hypothallus. Some of these branch repeatedly with flat anastomosing branchlets, ultimately fray out into lengthened threads, and perish after all the superstructure has been blown away. From every part of the structure so described, but more especially from the margins, are given off in profusion the strange cystiferous threads, so characteristic of this genus. These are exceeding delicate filaments, attached at one end, it may be, to a principal branch, at the other free or united to a second which again joins a third, and so looping and branching, dividing, they form a more or less extended network, a capillitium in which are entangled the myriad spores. Each filament bears at its middle point (or is it the meeting point of two?) a peculiar plexus which embraces several large cysts or vesicles whose function or further homology does not readily appear.

From the base of the fructification rise also ascending branches which are black, terete, and not infrequently branched as if to form the capillitium of a stemonitis. These ascending branches are in many cases, probably in all, real, though as yet imperfectly developed, columellae. They rise, at least in many cases, directly from the hypothallus, each is central to an individual sporangium, rises to about two-thirds its height, but never attains the summit. The sporangia are so crowded that many are choked off below, never reach the top of the aethalium. In such cases the columella may cease at the sporangium-top. The columella bears cystiferous threads sparingly, if at all; nevertheless these abound in the peripheral portions of the sporangium all the way up, and are especially noticeable beyond the level of the top of the columella. Many are so arranged that the plexus with its vesicles occupies a place in the plane separating adjacent sporangia, suggesting the possibility that we have here to do with an imperfectly developed surface-net and peridium. In this view the cysts would represent the meeting-point of two opposite radial capillitial threads rather than the middle of one. This accords with Rostafinski's observations and drawings. The cysts, then, belong morphologically to the peridium or sporangium wall. It is a stemonitis whose sporangia have never been perfectly differentiated, a case of arrested development. See further under _Stemonitis confluens_.

Rostafinski really offers the first definitive description. Fries probably distinguished it, but his description would not indicate the fact except for the added note wherein appears the reason for discarding an apparently older name, viz., that given by Link. But neither Link nor Sowerby distinguished by description or figure _Brefeldia_ from _Amaurochaete_.

Throughout the northern forest; Maine to Vancouver Island: not common.

=2. Stemonitis= (_Gleditsch_) _Rost._

1753. _Stemonitis_ Gleditsch, in part, _Meth. Fung._, p. 140.
1873. _Stemonitis_ (Gleditsch) Rost., _Versuch_, p. 7.

Sporangia distinct, though often closely aggregate, cylindric, stipitate; columella prominent; capillitium well developed by repeated lateral and apical branching of the columella, at length assuming at the surface the form of a distinct net which supports an evanescent peridium.

The genus is marked by its surface-net supported at the tips of the dichotomously branched divisions of the columella. Over the net is spread, theoretically at least, the peridial film supported by very short points projecting from the net,--the peridial processes; the peridium, however, is seldom seen; in some cases, certainly, is never developed. Rostafinski first defined the genus as employed by recent writers. Gleditsch simply renamed Micheli's _Clathroidastrum_; all writers subsequent included species of other genera.

The taxonomy of this genus is of the most difficult. Macroscopic, defining characters are few, and even these sometimes uncertain. Microscopic distinctions also tend to be illusive, variable in such fashion that often at the critical point the most exact description fails. All that may be done at present is to recognize two or three definite types and then cautiously differentiate among these with the light we have, until more general study of the group brings to service a wider range of observation with more comprehensive record on which judgment may better be sustained.

We have before us many and beautiful forms of this genus yet unstudied. Some of these doubtless have already found place in our growing taxonomic literature; some apparently undescribed; all to wait wider leisure or perhaps a younger hand.

The entire life-history of every form is none too much if we would set out with any hope of accuracy the genetic relationships for which taxonomy stands. Recently European students are making the color of the plasmodium a basis for species-discrimination, which is good so far. But plasmodic characters are at present unserviceable generally, for two reasons; they vary in the same species; and unfortunately, when most needed, they are unknown and inaccessible. The student is generally confronted by forms mature, the plasmodic stage already past.

=Key to the Species of Stemonitis=

_A._ Sporangia connately united.

_a._ Spores verruculose 1. _S. confluens_

_b._ Spores reticulate 2. _S. trechispora_

_B._ Sporangia at maturity distinct.

_a._ Spore-mass grayish black.

1. Larger, 8-12 mm. spores distinctly
reticulate or warted, but sometimes
nearly smooth 3. _S. fusca_

2. Spores reticulate and spinulose.

i. Spores adherent, clustered 4. _S. uvifera_

ii. Sporangia very tall, 15-20 mm.,
rigid 5. _S. dictyospora_

iii. Sporangia short, jet- or
violet-black 6. _S. nigrescens_

_b._ Spore-mass rich brown.

1. Columella central.

i. Sporangia shorter, 5-6 mm., spores
banded 7. _S. virginiensis_

ii. Sporangia 8-10 mm.; spores
verruculose 8. _S. webberi_

iii. Sporangia tall, 15-20 mm. or more 9. _S. splendens_

2. Columella eccentric, sporangium in
cross-section, angular 10. _S. fenestrata_

_c._ Spore-mass ferruginous; sporangia in
tufts.

1. Spores smooth or nearly so.

i. Sporangia pale, small, 3-5 mm.,
crowded, stipe unpolished 11. _S. smithii_

ii. Sporangia ferruginous; columella
regular 12. _S. axifera_

iii. Sporangia ferruginous; columella
proliferate just below the apex 13. _S. flavogenita_

iv. Sporangia, spore-mass,
dusky-purplish or brown.

O On dead wood.

o Scattered, apex blunt 14. _S. pallida_

oo Clustered, acuminate 15. _S. carolinensis_

OO On living leaves, preferably,
spore-mass brown 16. _S. herbatica_

1. STEMONITIS CONFLUENS _Cooke & Ellis._

PLATE XI., Figs. 4, 4 _a_, 5.

1876. _Stemonitis confluens_ Cke. & Ell., _Grev._, V., p. 51.
1894. _Stemonitis splendens var. confluens_ Lister, _Mycet._, p. 112.
1899. _Stemonitis confluens_ Cke. & Ell., Macbr., _N. A. S._, p. 114.
1911. _Stemonitis confluens_ Cke. & Ellis, List., _Mycet., 2nd ed._,
p. 147.

"Sporangia fasciculate, confluent on a persistent hypothallus, dark fuscous; peridia very fugacious; stipes united at the base, erect, furcate; spores large, brown, globose. On oak bark.

"The stems are branched in a furcate manner and confluent at the base, forming a compact tuft. The capillitium is membranaceous at the angles; spores very large compared with allied species, being 12 mu. The specimens were too fully matured for more satisfactory description."

Such is the original description of this unique and interesting species. The sporangia occur in close-set tufts or clusters, are distinct, separate at their tips and bases only; perhaps not always at base. The capillitium rises by branching from the columella, rather more prolific than usual, and combines to form a distinct superficial net of large even meshes. From the outer arcs of the bounding net spring rather long acute processes which should support the peridium. This, however, is altogether rudimentary. In most places there is no sign of peridium at all, but here and there between contiguous sporangia opposite processes unite and at their point of union a tiny circular disk of the peridial membrane appears. At intervals, therefore, over the entire sporangium are seen these small brown disks, each about equalling in diameter the size of the average mesh. At other points the sporangia do not seem at all coalescent, but where the opposing processes do meet the union is perfect and the little disk seen edgewise looks like some delicate counter strung upon a wire.

The interest attaching to this in view of what has been said about _Amaurochaete_ and _Brefeldia_ is obvious.

Under the lens the spores and capillitium are concolorous, dark fuscous, the spores distinctly verruculose, about 12.5 mu.

The original gathering here described was from New Jersey; twenty years later Mr. Ellis was so fortunate as to find again fine specimens all on oak bark. The sporangia are quite small, only 3 mm. high, when blown out concolorous with the habitat.

2. STEMONITIS TRECHISPORA (_Berk._) _Torr._

PLATE XX., Figs. 11, 11 _a_, 11 _b_, 11 _c_.

1909. _Stemonitis fusca_ (Roth) Rost. var. _trechispora_ (Berk.),
_Fl. Myxom._, Torrend, p. 141.
1911. _Stemonitis fusca var. trechispora_ Torr., List., _Mycetozoa,
2nd ed._, p. 144.

Fructification in form of aggregations of more or less coalescent, small, dark-brown or dull black, sessile sporangia; hypothallus continuous, well-developed; columella black, gently tapering to a point beneath the apex, the capillitial branches, irregular, few, but passing into an open rather evenly-meshed net, the mesh several times the spore-diameter, free-ending branch-tips not lacking; the spores by transmitted light distinctly brown, the epispore a beautiful reticulation, a dozen or more cells to the hemisphere, 10-12 mu.

This is entered sometimes as a variety of _S. fusca_ to which species relationship would seem remote. The differences lie in form, color and structure. The spores alone are distinctive; there are none such, so far, none just like them, elsewhere in the genus. Torrend and Lister both enter the form as varietal; why not set it out, and save questions? The habitat approaches that of _Amaurochaete_, but the sporangia are distinct.

For our specimens we are indebted to the kindness of Dr. Roland Thaxter. The specimens were taken in a half-dry marsh, near Cambridge.

Material from Toronto sent by Professor Faull is also provisionally here referred. The form has netted spores, but they are not quite the same. The structure besides is more that of an amaurochaete; it has the peculiar basal webs and band-like stipes at base, stipes that never rise from horizontal to perpendicular and characterize _Reticularia_ and especially _Brefeldia_ as well as the usual amaurochaete. See Plate XX., Figs. 9, 9_a_, 9_b_.

3. STEMONITIS FUSCA (_Roth_) _Rost._

PLATE VI., Figs. 4, 4 _a_, 4 _b_

1787. _Stemonitis fusca_ Roth, _Roem. Mag. Bot._, I., p. 26.
1875. _Stemonitis fusca_ (Roth) Rost., _Mon._, p. 193.
1892. _Stemonitis fusca_ Rost., Massee, _Mon._, p. 72.
1895. _Stemonitis fusca_ Roth, List., _Mycetozoa_, p. 110.
1899. _Stemonitis fusca_ (Roth) Rost., Macbr., _N. A. S._, p. 115.
1899. _Stemonitis maxima_ Schw., Macbr., _N. A. S._, p. 116.

Sporangia tufted, generally in small clusters 6-8 mm., the individual sporangia slender, cylindric, blue-black or fuscous, becoming pallid as the spores are lost, stipitate; stipe short, about one-fourth the total height, black, shining; hypothallus scanty, but common to all the sporangia; columella prominent, attaining almost the apex of the sporangium, freely branching to support the capillitial net; capillitium of slender dusky threads, which freely anastomose to form a dense interior network, and outwardly at length combine to form a close-meshed net; spores pale, dusky violet, usually beautifully spinulose-reticulate, but sometimes warted or spinulose only, or nearly smooth, 7-7.5 mu.

As here set out the description is intended to include _S. maxima_ Schw. of the former edition. Rostafinski, Mon. _l. c._, describes _S. fusca_ Roth. as having "spores smooth." Since most American gatherings have reticulated spores, and since Schweinitz described a black American species, his specific name seemed appropriate for all except smooth-spored forms.

In the meantime two things have happened; Mr. Lister has examined the specimens remaining in the Strasburg herbarium and finds them with reticulate spores. The statement quoted from the _Monograph_ evidently does not apply to _all_ of Rostafinski's material; but under the circumstances the name _fusca_ may easily take the field, especially since another discovery makes for the same conclusion. The evidence is good that _S. maxima_ Schw. was indeed the largest, i. e. perhaps, the _tallest_ stemonitis he ever saw! probably, as his scanty herbarium-remnant shows, _S. fenestrata_ Rex!

4. STEMONITIS UVIFERA _n. s._

PLATE XX., Figs. 8, 8 _a_, 8 _b_, 8 _c_.

Sporangia tufted, generally in medium-sized clusters much as in _S. fusca_. The individual sporangium 7-9 mm. high, dark, slender, brown, becoming dull black or pallid as the spores are lost, stipitate, the stipe about one-fourth to one-third the total height, black polished shining; hypothallus distinct, common to all sporangia, purple-brown, shining; columella distinct, attaining almost the summit of the sporangium but inclined to waver a little at last, in other words, flexuose toward the top, freely branching, the branches rather stout, anastomosing to support the capillitial net; the meshes larger, several times the spore-diameter, the spores sooty-brown, distinctly warted or spinulescent, about 7-8 mu, clustered in groups of four or more.

Mt. Rainier, Washington,--1914.

5. STEMONITIS DICTYOSPORA _Rost._

1873. _Stemonitis dictyospora_ Rost., _Mon._, p. 195; _Myc. Fen._,
pp. 114, 122.
1879. _Stemonitis dictyospora_ Rost., Mass., _Mon._, p. 83(?).
1888. _Stemonitis dictyospora_ Rost., _Sacc. Syl. Fung._, Vol. VII.,
p. 397.
1893. _Stemonitis castillensis_ Macbr., _Nat. Hist. Bull._, Vol. 11,
p. 381.

PLATE X., Figs. 5, 5 _a_, 5 _b_.

Sporangia crowded in colonies of unusual size, 4-8 cm., tall, rigid 18-25 mm., slender, erect, stipitate, black throughout; the columella prominent, reaching nearly to the apex, abundantly branched, the branches forming an intricate dark brown capillitium; the net large-meshed several times the spore-diameter; the spores reticulate, spinulose, clear violet, 7-8 mu.

We here recover as is believed one of Rostafinski's best-described species. Our material is from Nicaragua, by kindness of Professor Shimek. Its relationship is with _S. fusca_ where Rostafinski placed it. The phrase describing spore-color is his.

6. STEMONITIS NIGRESCENS _Rex._

1891. _Stemonitis nigrescens_ Rex, _Proc. Phil. Acad._, p. 392.
1911. _Stemonitis fusca_ Roth, Lister, _Mycetozoa, 2nd ed._, p. 143.

Sporangia gregarious, upon a common hypothallus, erect, small, cylindric, stipitate; stipe black, extremely short, about half a millimetre; columella reaching the apex; capillitium violet-black, darker near the surface, forming a complete superficial net at the lower part of the sporangium only, elsewhere irregular or vanishing; spore-mass nearly black; single spores violet-black under the lens, the epispore spinulose and reticulate, about 8 mu.

The author of this species remarks: "This species is noteworthy for its comparatively short stipes, its very spinulose spores, and its black or nearly black color, the slight violet tint being only apparent on close inspection, especially in fresh moist specimens."

It is a small but very beautiful form, at first sight to be mistaken for a short _S. fusca_, though much more intensely black. The capillitium is concolorous, the inner network of rather few open meshes, the outer of large hexagonal openings, the arcuate threads of which are remarkable for the size, and especially the number, of the peridial processes, as many as five or six sometimes appearing along one side of a single mesh. The stipe is very short, and the columella runs as a straight, gradually diminishing axis to the very apex of the sporangium. Total height 3-5 mm.

The English _Monograph_ includes this with _S. fusca_; but it seems quite distinct in size, habit, color, etc., and has been found in the mountainous regions of Virginia and North Carolina, as well as about Philadelphia.

7. STEMONITIS VIRGINIENSIS _Rex._

1891. _Stemonitis virginiensis_ Rex, _Proc. Phil. Acad._, p. 391.
1899. _Stemonitis virginiensis_ Rex, Macbr., _N. A. S._, p. 130.
1911. _Comatricha typhoides_ Rost., List., _Mycetozoa, 2nd ed._,
p. 158.

Sporangia erect, gregarious, from a common hypothallus, generally clustered, cylindric or elongate-ovate, stipitate; stipe black, shining; columella reaching the apex, where it blends with the capillitium; capillitium delicate, the meshes of the net small, scarcely greater than the diameter of the spores; spore-mass umber brown; epispores reticulated, with ten or twelve meshes to the hemisphere, 5-7 mu.

This is a beautiful, and, as it seems to us, a very distinct, species. The markings on the epispore are sufficient to identify it. These are conspicuously banded somewhat as the spores of _Trichia favoginea_, for example. In habit, size of the sporangia, and capillitial branching, this species recalls _Comatricha typhoides_ (Bull.) Rost. All the sporangia examined are, however, plainly stemonitis in type, possessing the characteristic superficial net.

Until further light this may stand as offered in the first edition. Miss Lister prefers to enter it, banded spores and all, with the comatrichas, on account of color, size and occasional default (?) of surface net.

Virginia, _Dr. Rex._

8. STEMONITIS WEBBERI _Rex._

PLATE XI., Figs. 6, 7, 8.

1891. _Stemonitis webberi_ Rex, _Proc. Phil. Acad._, p. 390.

Sporangia clustered, usually in small tufts 1 cm. wide, rusty brown in color, 8-10 mm., including the stipe, which is jet black, shining, and much expanded at the base; hypothallus continuous, well-developed, a thin, transparent pellicle; columella black, tapering upward, giving off at intervals the capillitial branches, and becoming dissipated just below the obtuse apex; inner capillitial network very open, the branches far apart, anastomosing but a few times before breaking into the surface net to form large, irregular meshes, 50-125 mu; spores minutely roughened, fuscous, 8-9 mu.

These three forms, 8, 9, 10, are sometimes entered as varieties of a single species. Dr. Rex himself was inclined to take that view. There is no doubt of close similarity; it is a question of clearness in our dealing with the subject.

All three forms occur abundantly in the Mississippi Valley, but are generally,--always, as it seems to the writer,--distinguishable by the hand-lens. If we take No. 9 as type, 10 has an eccentric columella; 8 is shorter, about 1 cm., of a different tint, Dr. Rex even says "spores ferruginous in mass". To the west and southwest, the capillitium becomes coarser, more decidedly brown. In short, however similar in presentation the phases may sometimes appear, it would seem that each at its best is distinct enough for immediate recognition.

West of the Mississippi River chiefly: Iowa, South Dakota, Nebraska, Kansas, Oklahoma, New Mexico, etc.

9. STEMONITIS SPLENDENS _Rost._

PLATE VI., Figs. 6, 6 _a_, 6 _c_, 7, 7 _a_.

1875. _Stemonitis splendens_ Rost., _Mon._, p. 195.
1880. _Stemonitis morgani_ Peck, _Bot. Gaz._, V., p. 33.
1893. _Stemonitis splendens_ Rost., Macbr., _Bull. Lab. Nat. Hist._,
Vol. II, p. 381.
1894. _Stemonitis splendens_ Rost., List., _Mycetozoa_, p. 112, in
part.
1899. _Stemonitis morgani_ Peck, Macbr., _N. A. S._, p. 118.
1911. _Stemonitis splendens_ Rost., List., _Mycetozoa, 2nd ed._,
p. 145.

Sporangia clustered irregularly, sometimes forming patches 6-10 centimetres or more in extent, rich purple-brown in mass, cylindric, long, 15-18 mm., stipitate; stipe black, polished, shining, rising from a common hypothallus, which extends as a thin silvery film beneath the entire colony, but does not usually transcend its limits; columella black, percurrent, sparingly branched; capillitium of fuscous threads, within forming a network very open, the branches scarcely anastomosing until they reach the surface where they form the usual net of small meshes, pretty uniform in size, and presenting very few small, inconspicuous peridial processes; spores brown, very minutely warted, about 8 mu.

This elegant species occurs not rarely on rotten wood, usually in protected situations, although sometimes on the exposed surfaces of its habitat. The sporangia attain with us unusual height, sometimes 2 cm.; plasmodia, 6-8 cm., in diameter. The clear brown tufts appear in the autumn, marvels of graceful elegance and beauty; at sight easily recognizable by the large size and rich color. In Iowa it is almost universally present on fallen stems of _Acer saccharinum_ Linn., and it appears to be widely distributed, by far the most beautiful of all this beautiful series.

New England to Iowa, South Dakota, Washington, and British Columbia. Professor Shimek brings a _dusky_ phase from Nicaragua!--the type?

The plasmodium is white on maple stems, more creamy on stems of linden, on which wood it is more rarely found: occasionally on ash-stumps; even on the fallen bark of trees preferred.

In 1875 in his famous _Monograph_, Rostafinski set out three species with "dusky violet spores". These are his Nos. 94, 95 and 96.

The first one of these he calls _S. fusca_, "spore-mass, etc., violet-black, individual spore clear violet, smooth, 7-9 u."

The second species he writes down _S. dictyospora_, "hypothallus, stalk, columella, capillitium and spore-mass, violet-black, spore netted and fringed, clear-violet, 7-9 mu."

The third species is _S. splendens_, "hypothallus stalk, columella and spore-mass violet-black, spore smooth, clear-violet, 7-8 mu."

It will be observed that in color down to color of the spore by transmitted light, the three species are exactly the same; constitute a suite, so to say. It has since turned out, as noted under our No. 3, that the spores of _S. fusca_ are netted. Error in description here is not surprising; the reticulations are sometimes faint. In _S. dictyospora_ they are admittedly strong, and the inference was that the '_gladkie_' spores of the third species might be netted also. This is no criticism: lenses were fifty years since not nearly so good for such discoveries as the oil-immersion is now.

However; Rostafinski made his specific diagnosis turn largely upon the mesh-width in the superficial net. This comes out in the '_opis_' following the description, and upon _this_ the European decision in Rostafinski's favor as against _S. morgani_ largely turns. Tropical gatherings are probably always darker, and evidently from such, from the north coast of South America, the original description was drawn. Specimens before us from the same latitude are dusky indeed; no clear brown at all, but purplish withal.

For the sake of harmony we may therefore now substitute the earlier name "with reservations"! but our description remains as before, presenting the really splendid, shining things that adorn our northern fields. Dr. Rostafinski called the large open meshes of the net '_oka_', eyes; _lumina_ let us say! quite uniform they are in 9 and 10, much less so in 8.

10. STEMONITIS FENESTRATA _Rex._

1890. _Stemonitis splendens_ R. _f. fenestrata_ Rex, _Proc. Phil.
Acad._, p. 36.

Sporangia aggregated, in tufts 2 cm. or more in diameter, rich purple brown, on a common hypothallus, more or less erect, stipitate, tall, about 2 cm., slender, triangular in section; stipe black, about one-third the total height, passing into a slender columella which is lateral in position, not central, but little branched, continued almost to the apex; the capillitium consisting almost entirely of the peripheral net, which presents meshes of unusual uniformity of size and shape; spores in mass brown, colorless by transmitted light, nearly smooth, 6-7.5 mu.

The remarkable shape of the sporangium and the peculiar regularity of the surface net, the lateral columella, all combine here to warrant the erection of a distinct species. Dr. Rex referred this to _S. baeuerlinii_ Mass. At that time he had not the author's description, and had seen only a very poor fragment received with notes in a letter. Mr. Massee's description makes it immediately evident that whatever other affiliations _S. baeuerlinii_ may have, by description it has at least none with _S. fenestrata_ nor with our northern form of _S. splendens_. Massee's species is described as having the "mass of spores black", the capillitium with "branches springing from the columella; the main branches more and more numerous, thicker and irregular towards the apex of the sporangium, and often form irregular flattened expansions":--etc. This suggests some form of _S. dictyospora_ Rost.: see under our No. 5. Possibly for such reasons Lister referred it to _S. splendens_ Rost., which as we have just seen, was undoubtedly regarded by the author as a form of the _fuscous_ group.

The long, slender, simple columella is not only lateral, but occupies indeed the sharp vertical angle of the triangular, prismatic sporangium. Furthermore, the sporangium is at maturity strangely twisted, so that the columella in its ascent accomplishes one or more spiral turns. In forms collected by Dr. Rex, which seemed to him most nearly to agree with Massee's species, the inner capillitium is somewhat abundant, but the character of the columella just the same.

Pennsylvania, Ohio, Kansas, Colorado, Iowa; India!

11. STEMONITIS SMITHII _Macbr._

1893. _Stemonitis smithii_ Macbr., _Bull. Lab. Nat. Hist. Ia._, II.,
p. 381.
1894. _Stemonitis microspora_ List., Morg., _Jour. Cin. Soc._, p. 54.
1911. _Stemonitis ferruginea_ var. _smithii_ Lister, _Mycetozoa,
2nd ed._, p. 150.

Sporangia in small clusters, close-packed and erect, not spreading, bright ferruginous prior to spore dispersal, cylindric, stipitate, of varying height; stipe jet-black, shining, about one-third the total height; hypothallus generally well developed; columella black, gradually tapering, at length dissolving in capillitial threads and net some distance below the diminished plumose apex; capillitium of fuscous threads, the inner network of abundant, sparingly united branches uniformly thickened, the surface net very delicate, composed of small, regular, polygonal meshes, the peridial processes few; spore-mass bright ferruginous, spores by transmitted light pale, almost colorless, smooth, 4-5 mu.

The species as thus constituted includes forms varying in size from 2.5-3 mm. only. The common form heretofore known everywhere in America as _S. ferruginea_ is from 10-15 mm. high. The _type_ to which the specific name _S. smithii_ was originally applied is 2.5 mm. high and rejoices in smooth, almost colorless spores, 4-5 mu.

The plasmodium in the case of the species now considered is as concerns the _type_, of course, unknown. In one or two gatherings referred here the color of the plasmodium was noted greenish-yellow. This has the look of _S. flavogenita_; but small spores and delicate make-up take it the other way. Miss Lister makes it varietal to No. 12, next following.

12. STEMONITIS AXIFERA (_Bull._) _Macbr._

PLATE VI., 5, 5 _a_, and 5 _b_.

1791. _Trichia axifera ferruginea_ Bull., _Champ. de la Fr._, p. 118,
tab. 477.
1818. _Stemonitis ferruginea_ Ehr., _Syl. Myc. Berol._, p. 20;
et auct. Europ. ex parte; Americ., non.
1894. _Stemonitis ferruginea_ Ehr., List., _Mycetozoa_, p. 115,
in part.
1899. _Stemonitis axifera_ (Bull.) Macbr., _N. A. S._, p. 120,
in part.
1911. _Stemonitis ferruginea_ Ehr., Lister, _Mycetozoa, 2nd ed._

Sporangia terete, acuminate, fasciculate small in dense clusters, distinctly ferruginous in color, stipitate, from 10-15 mm. in height; the stipe black one-third to one-half the total height, not shining or polished; columella evenly branching, dissipated before reaching the acuminate apex; capillitium-branches clear brown anastomosing and dividing more or less to bear the superficial fine-meshed net; spores pallid, faintly ferruginous, smooth or nearly so, 5-6 mu.

This would seem to be the common _ferruginous_ species of the world. Doubtless Micheli had the thing before him when he drew Tab. 94, _clathroidastrum_, Hoffman and Jacquin seem to have recognized the form. To be sure, under the present plasmodic limitations we cannot be quite certain about these references. Not until 1791 does anyone write down a particular species as marked by a white plasmodium, and distinguish it from other similar fructifications having similar origin. Bulliard, _l. c._, does this, discriminating between _T. axifera ferruginea_ and _C. typhoides_; see under the last-named species. Youthful Ehrenberg, in his doctor's thesis, nearly thirty years later, draws a similar parallel but ignores the great French author, writing _S. ferruginea_ Ehr. as though the thing had never been seen before! By this name it has been called until very lately; Fries accepting it, but noting that the plasmodium, for him at least, was _yellow_!

In 1904 Dr. E. Jahn, following Fries' suggestion, established the fact that Ehrenberg's white-plasmodic species had small spores, that Fries had in mind a form with larger spores, having indeed yellow plasmodium; but see number 13 below.

It is for the present assumed that the plasmodium of our American _S. axifera_ is white. So far, there are few or no observations which establish the fact. The color, the small smooth spores, the fine-meshed capillitial net and the general dimensions determine the reference.

13. STEMONITIS FLAVOGENITA _Jahn._

PLATE XX., Figs. 10, 10 _a_, 10 _b_.

1829. _Stemonitis ferruginea_ Ehr., Fries, _Myc._ III., p. 158,
Syn. excl.
1899. _Stemonitis axifera_ (Bull.) Macbr., _N. A. S._, p. 120,
in part.
1904. _Stemonitis flavogenita_ Jahn, _Abh. Bot. Ver. Brandenb._,
XLV, p. 265.
1911. _Stemonitis flavogenita_ Jahn, List., _Mycetozoa, 2nd ed._,
p. 149.

Sporangia cylindric, obtuse, closely fasciculate, "cinnamon brown," stipitate, 5-7 mu; stipe short, black, columella ceasing abruptly below the apex; capillitium a loose net-work with many broad expansions; the peridial net very delicate, the meshes small but uneven, 6-15 mu, with many projecting points; spores pale ferruginous, verruculose, 7-9 mu.

This is _S. ferruginea_ Ehr. of Fries with its plasmodium yellow. Fries says "flavicat," _becomes_ yellow, if one may follow the analogy of corresponding Latin verbs of color, so that the record of color-changes in the present species is yet to be recorded.

Until further experience may advise to the contrary, we may assume that all stemonites cinnamon-brown in color, with widened columella-tip, and pale yellowish spores 7-9 mu in diameter, have at some time in their history a yellow plasmodium, and accordingly represent in America the new-found species.

The larger spores, and, the strange proliferate development of the columella-tip, to which Miss Lister has happily called attention, constitute the essential diagnostic features here.

Our only specimens so far are from Oregon.

14. STEMONITIS PALLIDA _Wingate._

PLATE XIII., Fig. 3

1897. _Stemonitis pallida_ Wing., _N. A. F._, Ell. and Ev., No. 3498.
1899. _Stemonitis pallida_ Wing., Macbr., _N. A. S._, p. 123.
1911. _Stemonitis pallida_ Wing., List., _Mycetozoa, 2nd ed._, p. 149.

Sporangia gregarious, or somewhat clustered, erect, cylindric obtuse, short, blackish brown, rubescent, becoming pallid, stipitate; stipe short, black, polished, rising from a thin, brown, or iridescent hypothallus; columella percurrent, ceasing abruptly at the apex; capillitium filling the interior with abundant branches which form at the surface a close-meshed net, little developed above, making the apex very blunt; spores in mass, dark brown, by transmitted light dusky, nearly smooth, 7.5 mu.

This species is well recognized at sight, among the fuscous forms, by its scattered, erect habit. In color it is not unlike _S. fusca_, but has an added reddish tinge. In form it is peculiar by virtue of the blunt rounded apex which seems to be a constant character. The spores under moderate lens are perfectly smooth, under the 1-12 they present very delicate low scattered papillae.

Rare; eastern part of United States.

15. STEMONITIS CAROLINENSIS _Macbr._

PLATE XIII., Fig. 5.

1894. _Stemonitis tenerrima_ Berk. & C., Morg., _Jour. Cin. Soc._,
p. 53.
1899. _Stemonitis carolinensis_ Macbr., _nom. nov._, _N. A. S._,
p. 152.
1911. _Stemonitis pallida_ Wing., Lister, _Mycetozoa, 2nd ed._,
p. 149.

Sporangia tufted in scattered clusters, small, slender, cylindric but tapering from the apex, at first ferruginous then ashen or purplish, stipitate; the stipe short, black and shining, one-fourth the total height or less, even; hypothallus well developed, black or very dark brown; columella black, gradually diminishing, at length dissipated some distance below the clavate or acuminate apex of the sporangium; capillitium dense, the inner of many, scarcely expanded, pallid, freely anastomosing branches, the outer a net of very small meshes, often less than the spores, 3-15 mu, peridial processes imperceptible; spore-mass pale ferruginous, spores by transmitted light pale violaceous brown, smooth, 6-7 mu.

Very closely related to the preceding, but recognizable by its proportionately much more slender, taller, acuminate sporangia, paler, and denser capillitium and the remarkably close-meshed net.

Not uncommon south: Kentucky, Alabama.

16. STEMONITIS HERBATICA Pk.

PLATE XVI., Figs. 14, 14 _a_, 14 _b_.

1874. _Stemonitis herbatica_ Peck, _Rep. N. Y. Mus._, XXVI., p. 75.
1899. _Stemonitis axifera_ (Bull.) Macbr., _N. A. S._, p. 120,
in part.
1911. _Stemonitis herbatica_ Pk., Lister, _Mycetozoa_, p. 148.

Sporangia clustered, in scattered tufts, cylindric, obtuse, pallid ferruginous, stipitate or sometimes nearly sessile; stipe fuscous or jet-black, only slightly expanded below, much shorter than the columella; hypothallus scanty or none; columella lessening upward, sometimes attaining the apex of the sporangium, sometimes dissolved in capillitial threads some distance below; capillitium of rich brown threads forming the usual inner network of medium density, with many wide expanded nodes, the surface net made up of delicate, almost colorless threads surrounding small polygonal meshes; spore-mass ferruginous, spores by transmitted light very pale, brownish, minutely warted, 7-9 mu.

The plasmodium of this species is variously cited from white to yellow. Probably each report is true, dependent on the relative time of the observation.

The low tufts of brown sporangia with short black stipes, borne often as Dr. Peck found them, assembled on living leaves, distinguish this little species. In the former edition this form was tentatively enrolled under _S. axifera_ (Bull.); but see further under that species.

Probably widely distributed, but confused with short forms of other species; sometimes also on rotten wood or other substratum; so reported.

New York to Iowa; Washington and Oregon. Reported also from Europe.

=3. Comatricha= (_Preuss_) _Rost._

1851. _Comatricha Preuss_, _Linnaea_, XXIV., p. 140.
1873. _Comatricha_ Rostafinski, _Versuch_, p. 7.

Sporangia cylindric or globose, stipitate; stipe prolonged upward to form a more or less extended and tapering columella bearing branches on every side, which by repeated divisions and reunions form the capillitium; ultimate branch-tips free, not supporting a surface net parallel to the peridial wall; peridium evanescent, perhaps sometimes not developed at all.

The genus _Comatricha_ was set off from _Stemonitis_ by the joint effort of Preuss (1851) and Rostafinski (1873-5). Preuss included in his genus, _Comatricha_, alien forms, and besides failed to give an accurate definition; included, however, in his list some species which have since been known by his generic name.

The distinction between the two genera is almost an artificial one, and species are sometimes arbitrarily assigned to one genus or the other. The diagnosis in any case turns upon the presence or absence of a surface net, formed, in _Stemonitis_, by the anastomosing of the ultimate divisions of the capillitial branches. In _Comatricha_ the anastomosing is general, from the columella out, and is not specialized at the surface.

Recent attempts to reunite the genera here compared seem to result in no apparent advantage. The genera come very near together, but their separation along the line suggested by Rostafinski remains convenient.

=Key to the Species of Comatricha=

_A._ Sporangia closely clustered.

_a._ Obovate or short cylindric.

1. Spores verruculose 1. _C. caespitosa_

2. Spores reticulate 2. _C. cylindrica_

_b._ Elongate, reddish-brown, tufts extended 3. _C. flaccida_

_B._ Sporangia scattered more or less widely.

_a._ Capillitium lax, open.

i. Sporangia long, 10-12 mm. 4. _C. longa_

ii. Sporangia shorter, capillitium
irregular 5. _C. irregularis_

_b._ Capillitium dense.

i. Sporangia large, to 10 mm., spore-mass
black 7. _C. suksdorfii_

ii. Sporangia smaller--6 mm.

O Spore-mass brown, spherical,
conoidal, etc., generally with
more or less lengthened stipe 8. _C. nigra_

OO Spore-mass violaceous or purplish 9. _C. aequalis_

iii. Sporangia ovate or cylindric, minute,
to 3.5 mm.

O Cylindric, spore with few,
scattered warts 10. _C. typhoides_

OO Smaller, capillitium irregular,
loose 6. _C. laxa_

OOO Total height to 2 mm. or much less.

+ Columella digitately divided 11. _C. elegans_

++ Columella lamprodermoid, and on
leaves 12. _C. rubens_

+++ Columella stemonitoid 13. _C. pulchella_

++++ Columella furcate at tip 14. _C. ellisii_

+++++ Columella almost percurrent. 15. _C. subcaespitosa_

1. COMATRICHA CAESPITOSA _Sturgis._

PLATE XI., Figs. 12, 13, 14.

1893. _Comatricha caespitosa_ Sturg., _Bot. Gaz._, XVIII., p. 186.
1894. _Diachaea thomasii_ Rex, var., List., _Mycetozoa_, p. 92.
1899. _Comatricha caespitosa_ Sturg., Macbr., _N. A. S._, p. 124.
1911. _Diachaea caespitosa_ Lister, _Mycetozoa, 2nd ed._, p. 121.

Sporangia densely crowded or cespitose, sub-sessile or short stipitate, clavate, 1-1.5 mm. high, the peridium gray, iridescent with blue tints, comparatively permanent but finally disappearing; columella attaining two-thirds to three-fourths the height of the sporangium, giving rise throughout its length to the dense blackish capillitium; hypothallus delicate, inconspicuous; capillitium, the main branches thick at the point of origin, frequently anastomosing, and becoming gradually thinner toward the surface of the sporangium, the tips pointed, free, forming the network; spores blackish-violet in mass, by transmitted light pale brownish-violet, rough, 9.5-13 mu.

A very distinct and curious species. The sporangia are densely crowded, though by the nature of habitat somewhat tufted. The shape of the individual sporangium is quite uniformly clavate or obovate, decidedly truncate above. The spores are uniformly verruculose and plainly unequal.

This species, as indicated, was by its author described as a comatricha. To transfer it to another genus seems idle, especially when long established generic boundaries must be seriously disturbed expressly to admit the new arrival.

New England, North Carolina, on moss and lichens.--_Dr. Sturgis._

2. COMATRICHA CYLINDRICA (_Bilgram_) _Macbr._

1905. _Diachaea cylindrica_ Bilgram, _Proc. Acad. Nat. Sci. Philad._,
524.
1911. _Diachaea cylindrica_ Bilgram, List., _Mycetozoa, 2nd ed._,
p. 121.

Sporangia cylindrical with obtuse apex, sessile, gregarious, iridescent, steel-gray or bronze, 1 to 1.7 mm. high, .5 to .65 mm. thick; hypothallus whitish, rugose; sporangium-wall membranous, hyaline, not adhering to the capillitium; columella arising from the hypothallus and extending nearly to the apex, brown, very light and semi-translucent near the base, irregular, flexuous, limeless throughout; capillitium brown, radiating from the columella to the periphery, repeatedly branching and anastomosing; spores warted, the warts connected by ridges forming a more or less perfect, coarse reticulation, violaceous, pale, 10-12 mu.

This is a very interesting species closely related to the preceding from which it differs chiefly in the reticulation and generally more uniform character of the spores. The author hesitated about the generic reference, finally referring it to _Diachaea_ despite the lack of calcium, because it was sessile and had a peridium rather more persistent than is usual in comatrichas. But the presence of lime in stipe and columella is an essential element in the diagnosis of _Diachaea_, while length of stem is everywhere variable in stipitate forms of every genus, and the persistence of the peridium is also an uncertain factor; hangs on long in _C. typhoides_, _e. g._

On dead twigs, etc.--Philadelphia,--_Mr. Bilgram_; New Hampshire.

3. COMATRICHA FLACCIDA _List._

1894. _Comatricha flaccida_ List., Morg., _Jour. Cin. Soc._, p. 51.
1894. _Stemonitis splendens_, var. _flaccida_ List., _Mycetozoa_,
p. 112.
1894. _Comatricha flaccida_ (List.) Morg., Macbr., _N. A. S._, p. 133.
1911. _Stemonitis splendens_, var. _flaccida_ List., _Mycetozoa,
2nd ed._, p. 146.

Sporangia semi-erect, close crowded in tufts two inches in diameter, ferruginous, from a dark brown hypothallus, sessile or short stipitate; columella weak, crooked, percurrent, generally enlarged irregularly at the apex; capillitium of few, slender, brown branches which anastomose sparsely and irregularly as in _C. irregularis_, and present when freed from spores the same chenille-like appearance; spore-mass ferruginous brown; spores by transmitted light bright reddish brown, minutely warted, 8-10 mu.

"Growing on old wood and bark of Oak, Willow, etc. The component sporangia 5-10 mm. in length. The early appearance is much like that of a species of _Stemonitis_, but the mature stage is a great mass of spores with scanty capillitium, as in _Reticularia_; the columellas, however, are genuine and not adjacent portions of wall grown together."--_Professor Morgan._

Professor Morgan's herbarium material is at hand for study. It meets his description, needless to say, very generally. In what remains of the type the membranous connections are obscure; in fact the relation of such peridial (?) fragments to the capillitium in any way, is no longer evident. But in any event the colony does not impress one as something prematurely or improperly developed, a stemonitis gone begging;--nothing of that kind; it is clearly a comatricha, easily identifiable with no trace of a surface net but, with long free tips in plenty.

Misled no doubt, by the peridial fragments referred to, Mr. Lister in _Mycetozoa, l. c._, associated this with _S. confluens_ Cke. & Ell., but entered it as a variety of _S. splendens_ Rost., just the same. In the second edition of the _Monograph_, Ellis' species is set out, but Morgan's retains the old position.

In light of present knowledge, the relationship suggested would be difficult of proof. If _C. flaccida_ Morgan be related to the _splendens_ group at all, it must be with the form known as _S. webberi_ Rex., but it differs from this in almost every particular. It has no net, with meshes uniform or diverse; it is clear brown in color, with a tinge of red, beneath the lens; the spores are smaller, distinctly warted and with the reddish tinge of the capillitium; and in short, it seems to be a comatricha and not a stemonitis.

Specimens from western Washington differ in some particulars but are apparently the same thing.

Ohio, Kentucky, Washington, California; not common.

4. COMATRICHA LONGA _Peck._

PLATE VI., Figs. 2, 2 _a_, 2 _b_.

1890. _Comatricha longa_ Peck, _Rep. N. Y. Mus._, XLIII., p. 24.

Sporangia crowded in depressed masses or tufts, black, long, cylindric, even, stipitate; stipe black, shining, generally very short; hypothallus well developed, black; columella black, slender, weak, generally dissipated some distance below the apex; capillitium of slender brown or dusky threads anastomosing to form an open network next the columella, but extended outwardly in form of long free slender branchlets, now and then dichotomously forked; spore-mass blue-black, spores by transmitted light dark brown, globose, spinulose, some of them faintly reticulate, about 9 mu.

A very remarkable species. Rare in the west, more common, as it appears, in the eastern states. The sporangia occur in tufts about 1 or 2 cm. wide, springing generally from crevices in the bark of decaying logs, especially willow and elm, in swampy places. The sporangia are remarkable for their great length. Generally about 20-25 mm., specimens occasionally reach 50 mm.! The capillitial branches are so remote that the spores are scarcely retained by the capillitium at all. Well described and figured by the author of the species, _Forty-third Rep. N. Y. State Museum_, p. 24, Pl. 3.

New York, Pennsylvania, Ohio, Iowa.

5. COMATRICHA IRREGULARIS _Rex._

1891. _Comatricha irregularis_ Rex, _Proc. Phil. Acad._, p. 393.

Sporangia crowded in flocculent tufts, very dark brown or black, semi-erect or drooping, 4-5 mm. in height, irregularly cylindric, variable, stipitate; stipe black, distinct, often one-half the total height; hypothallus well developed, brown, shining; columella central, slender, flexuous, reaching the apex, where it blends, by branching, with the capillitium; capillitium loose, open, composed of arcuate threads which radiate from the columella, and are joined together, forming a central, irregular reticulation of large meshes, brown, paler toward the surface, where the free ends are sometimes colorless; spore-mass black, spores by transmitted light brown, minutely warted, 7-8 mu.

Related, no doubt, to _C. longa_, but differing in habit, stature, as in texture and structure of the capillitium. In _C. longa_ the inner net is extremely simple,--a row or two of meshes at most, and the radiating branches are long and straight; in the species before us the inner network is well developed, and the radiating branches proportionately shorter and abundantly branching, with pale or white free tips.

Generally, though not always, found growing in the crevices of the bark on fallen logs of various deciduous trees. September. Not common.

This is thought to be _C. crypta_ Schw., _N. A. F._, 2351; but the description under that number does not make clear what form Schweinitz had before him, the present species or _C. longa_, and the herbarium specimen of Schweinitz is "utterly lost"; the later specific name is accordingly adopted.

New England west to the Cascade Mountains; south to Kansas and Texas.

6. COMATRICHA LAXA _Rostafinski._

PLATE V., Figs. 5, 5 _a_.

1875. _Comatricha laxa_ Rost., _Mon._, p. 201.
1877. _Lamproderma ellisiana_ Cooke, _Myx. U. S._, p. 397.
1891. _Comatricha ellisiana_ (Cooke) Ell. & Ev., _N. A. F._, 2696.

Sporangia scattered, gregarious, sub-globose or short cylindric, and obtuse, dusky stipitate; stipe short, black, tapering rapidly upward from an expanded base; hypothallus scant or none; columella erect, rigid, sometimes reaching nearly to the apex of the sporangium, sometimes dichotomously branched a little below the summit, before blending into the common capillitium; capillitium lax, of slender, horizontal branches, anastomosing at infrequent intervals and ending in short, free tips; spores pallid, nearly smooth, 7-9.5 mu.

A very minute, delicate little species, about 1-1/2 mm. high; the stipe half the total height. In general appearance the shorter forms of the species resemble slightly _C. nigra_, but are distinguished by a much shorter stipe and much more open capillitium. The sporangia of _C. nigra_ mounted on long capillary stipes always droops more or less; the sporangia of the present species stand rigidly erect. The sporangia vary in form and in the branching of the columella. In the more globose phases, the columella almost always shows a peculiar dichotomy near the apex; in the cylindric types, this peculiar division fails.[36] In fact, the shape is determined chiefly by the mode of branching as affects the columella. Rostafinski's figure, on Tab. XIII, does not present the type usually seen in this country, nor even in Europe if we may judge from later illustrations.

The species with us has received various names, but so far as can be determined, all apply to the same thing, and comparison of specimens from Mr. Ellis with those from Europe show the correctness of the nomenclature here adopted.

Rare, but widely distributed; across the continent.

7. STEMONITIS SUKSDORFII _Ell. & Everh._

PLATE XI., Figs. 9, 10, 11.

1882. _Stemonitis suksdorfii_ Ell. & Everh., _Bull. Washb. Coll._,
Vol. I., p. 5.
1892. _Stemonitis suksdorfii_ Ell. & Everh., Mass., _Mon._, p. 76.

Sporangia scattered in small tufts or gregarious, cylindric, obtuse at both ends, sometimes widened above, black, 2-6 mm., stipitate; stipe jet-black, shining, even, about one-half the total height; hypothallus not continuous, dark brown; columella black, rather slender, terminating in two or more large branches just below the apex; capillitium exceedingly dense, dark fuscous or black, the flexuous threads anastomosing in a close network, with abundant free pallid extremities; spores in mass, blue-black, by transmitted light fuscous or dark violaceous-brown, minutely warted, 10-12 mu.

Easily recognizable at sight by its sooty color. Entirely unlike any of the preceding. The type of the capillitium is that of _C. pulchella_, but it is very much more dense and entirely different in color. The sporangia are often widened above, and fairly truncate; the total height about 6 mm. Found on the bark of fallen twigs of _Abies, Larix_, etc. Distributed by Ell. & Everh. under this name as an _exsiccata_. The evanescent peridium is colorless; when free, white or silvery.

8. COMATRICHA NIGRA (_Pers._) _Schroeter._

PLATE XI., Figs. 1, 2, 3.

1791. _Stemonitis nigra_ Pers., Gmel., _Syst. Nat._, p. 1467.
1801. _Stemonitis ovata_, var. _nigra_ Pers., _Syn._, p. 189.
1863. _Stemonitis friesiana_ DeBy., _Rab. Eur. Fung._, No. 568.
1875. _Comatricha friesiana_ (DeBy.) Rost., _Mon._, p. 200.
1889. _Comatricha nigra_ (Pers.) Schroeter, _Pilz. Krypt. Fl.
v. Schles._, I., p. 118.
1894. _Comatricha obtusata_ Fr., Lister, _Mycetozoa_, p. 117.
1899. _Comatricha nigra_ (Pers.) Schroeter, Macbr., _N. A. S._,
p. 128.

Sporangia scattered, ferruginous or dark brown, globose or ovoid, stipitate; stipe long, hair-like, tapering upward, black; hypothallus none; columella rapidly diminished toward the top, at length dissipated; capillitium of slender flexuous threads, radiating horizontally, repeatedly branching and anastomosing to form an intricate dense network, from the surface of which project a few short hook-like peridial processes; spore-mass black, spores by transmitted light dark violaceous, smooth or nearly so, 7-10 mu.

This species, when typical, is easily recognized by its almost globose sporangia mounted on long slender stocks. These are 2 or 3 mm. high and generally persist, as Persoon noticed, a long time after the sporangium has fallen. The sporangia are at first black; after spore disposal pale ferruginous. In shape they vary from ovate to spherical. Sometimes they are umbilicate below, so that a vertical section would be obcordate. Care must be taken to distinguish the present species from blown-out forms of _Lamproderma_.

This most common species seems to be also the center of widest differentiation. In a valuable paper on the Myxomycetes of Dr. C. H. Peck's Herbarium Dr. Sturgis points out the varying relationships of a group of surrounding forms. According to account _C. nigra_ verges on one side to _C. laxa_, on the other to _aequalis_ which the Listers enter as varietal here. However, in the former the more rigid, direct and simple branching from the columella is usually determinative; in the latter the color, form, and generally more delicate structure, and a tendency to grow in tufts will serve to distinguish.

In this discussion we have assumed as typical the globose sporangium, with the variations in the direction of ovate, obovate, ellipsoidal, etc., the capillitium flexuous and more richly anastomosing near the columella. On the drier slopes in the mountains of Colorado specimens are especially abundant, in proper season covering apparently the lower surface of every barkless twig or fallen stem or _tree entire_! In such a field one might imagine every possible variation open to observation. Probably such is the case; but as a matter of fact a single small plasmodium at lower levels will sometimes show greater range of variation than were noted on the mountain-side. The cylindric forms were for some reason few, and when noted were short, though often surmounting stems of double the usual length.

Rostafinski calls this _C. friesiana_, a name suggested by De Bary. By this name the species was commonly known for many years. More recently some writers prefer _C. obtusata_ Preuss; but _C. obtusata_ Preuss, as figured by that author (Sturm's _Deutsch. Fl._, Pl. 70), is surely more likely _Enerthenema papillata_, and the author says in his description "capillitio vertice soli innato." Persoon certainly recognized the species, and his description, though brief, is yet applicable to no other European species. There seems no reason why the name he gave should not be permanently adopted. Rostafinski's figure, Tab. XIII., shows an ellipsoidal sporangium, not cylindric.

On the lower levels of the Mississippi valley, the species is not common. Possibly overlooked by reason of its minuteness.

Massachusetts, Pennsylvania, Ohio, Iowa, Colorado, North Carolina, Missouri.

9. COMATRICHA AEQUALIS _Peck._

PLATE VI., Figs. 3, 3 _a_, 3 _b_, 3 _c_, 3 _d_; and PLATE XVIII., Figs. 13, 13 _a_, 13 _b_.

1890. _Comatricha equalis_ Peck., _Rep. N. Y. Mus._, XXXI., p. 42.

Sporangia gregarious, seldom erect, usually inclined, curved or nodding, dark brown, becoming violet, cylindric, acuminate-obtuse, stipitate; stipe about half the total height, 2-2-1/2 mm., black, polished, even; hypothallus well developed, brown, continuous; columella black, tapering gradually, and attaining almost the summit of the sporangium; capillitium dense, of flexuous tawny threads which, by repeated branching, form an intricate network, the free extremities numerous, short, and pale; spores dark violaceous, distinctly warted, 7.5-8 mu.