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_