Chapter XIII: Section 2: =Tilmadoche= Fries (6)

Sporangia gregarious, generally rounded or cushion-shaped, depressed, sessile, iridescent bronze, 1 mm. in diameter; peridium thin, translucent, opening irregularly; capillitium of simple threads, not netted, but often forked two or three times, taut, running from base to top; spores yellow, by transmitted light pale yellowish, minutely roughened, 8-10 mu.

This interesting species was collected in Orono, Maine, in 1889, by Professor F. L. Harvey, and so far as can be learned has not been taken since. Mr. Lister records two species from England which he refers to this genus. As to its systematic place, Dr. Rex says, _l. c._ "It stands as a single representative of a new and separate family adjoining the _Perichaenacae_ in the order _Calonemeae_ of Rostafinski."

Rare. Maine.

2. DIANEMA CORTICATUM _List._

PLATE XVI., Figs. 5 _a_, 5 _c_.

1894. _Dianema corticatum_ List., _Mycetozoa_, p. 205.

"Plasmodium pink"; sporangia sometimes flat-hemispheric, more often ill-defined, united in irregular, depressed, netted plasmodiocarps, generally dull brown; peridium opaque, didermatous, capillitium of simple or rarely branching filaments, variously beaded or marked with spiral bands, lightly attached at either end, occasionally twisted together; spore-mass dull brown, the spores in clusters of four or more, colorless by transmitted light, more or less verruculose, ellipsoidal, about 8-10 mu.

Our specimens are from the mountains of Alberta.

A curious, flat plasmodiocarp, an inch or more in length. It suggests _Hemitrichia serpula_ prematurely dry.

3. DIANEMA ANDERSONI, _Morg._

_Dianema andersoni_, _Morg._ MS., _non. pub._

Sporangium globose, sessile or sub-stipitate, seated on a thin brownish hypothallus; the wall a thin smooth pinkish membrane, when dry rugulose and iridescent, the inner surface somewhat thickened below and brownish at the base. Capillitium arising out of the thickened base, the threads hyaline or pinkish, ascending, flexuous, simple, or branched a time or two, the extremities attached on all sides to the wall of the sporangium. Spores globose, very minutely warted, pale, pinkish, 10-11 mu, in diameter, free.

Growing on old wood and bark of _Alnus_; British Columbia, _W. B. Anderson_.

Sporangium spherical, 6-8 mm. in diameter, sessile or on a very short stipe. This species differs from D. harveyi Rex in the _uniform pinkish_ color of the wall and of the spores; the dividing threads are furnished remotely with minute roundish tubercles as in _Didymium_; the spores are somewhat larger than in _D. harveyi_.

_B._ PERICHAENACEAE

=Key to the Genera of the Perichaenaceae=

_A._ Sporangia more or less plasmodiocarpous in type,
terete; dehiscence irregular 1. OPHIOTHECA

_B._ Sporangia more or less polygonal in outline, or
round, depressed; dehiscence circumscissile 2. PERICHAENA

=1. Ophiotheca= _Currey_.

1869. _Ophiotheca pallida_ Berk. & C., _Jour. Linn. Soc._, X., p. 350.

Fructification generally plasmodiocarpous, terete, bent or flexuous, often annular or cornuate, rarely globose, opening irregularly, peridium thin, not polished, covered more or less strongly with a distinct layer of scales or granules; capillitium of slender, loosely branching filaments, the surface rough to strongly spinulose; spores yellow.

As a generic name _Ophiotheca_ plainly has priority. _Cornuvia_ as understood by Rostafinski has no representative so far in our region.

=Key to the Species of Ophiotheca=

_A._ Plasmodiocarp usually upon herbaceous stems,
slender 1. _O. vermicularis_

_B._ Plasmodiocarp on rotting bark, logs, etc,

_a._ Pale brownish or yellowish 2. _O. chrysosperma_

_b._ Chestnut brown or blackish 3. _O. wrightii_

1. OPHIOTHECA VERMICULARIS (_Schw._) _Macbr._

1834. _Physarum vermicularis_ Schw., _N. A. F._, No. 2296.
1869. _Ophiotheca pallida_ Berk. & C., _Jour. Lin. Soc._, X., p. 350.
1873. _Ophiotheca umbrina_ Berk. & C. Grev., II., p. 88.
1876. _Perichaena pallida_ (Schw.) Rost., _Mon. App._, p. 34.

Plasmodiocarp very slender, terete, elongate, flexuous or reticulate, annular, etc., of dull gray or neutral tint; the peridium thin, translucent, but with a delicate granular outer coating; capillitium of slender threads, frequently branched, warted and usually minutely spinulose; spore-mass ochraceous yellow; spores by transmitted light pale yellow, minutely roughened, 10 mu.

Perhaps common, but seldom collected, probably overlooked on account of protective coloration; the color is about that of the habitat, the weathered surface of dead herbaceous stems and roots. On dead corn stalks not infrequent. Differs from other species of the genus in having smoother capillitium, for which reason Rostafinski calls the present species _Perichaena vermicularis_. _O. pallida_ Berk. & C. seems to us to be the same thing, _N. A. F._, 726.

New England, New Jersey, South Carolina, Ontario, Ohio, Iowa.

2. OPHIOTHECA CHRYSOSPERMA _Currey_.

1854. _Ophiotheca chrysosperma_ Currey, _Quart. Mic. Jour._, II.,
p. 240.
1875. _Cornuvia circumscissa_ (Wallr.) Rost., _Mon._, p. 290.
1911. _Perichaena chrysosperma_ Lister, _Mycetozoa, 2nd ed._, in
part, p. 248.

Plasmodiocarp elongate, bent and curved in various ways, spherical, more rarely annular or even reticulate, yellowish or ochraceous brown, opening irregularly; peridium thin, with yellowish outer layer; capillitium rather abundant, of threads slender, sparingly branched and minutely but distinctly spinulose; spore-mass yellow, spores by transmitted light pale, almost smooth, about 8 mu.

Occurs on the inner bark of deciduous trees, especially of oak. Not common.

This is possibly _Cornuvia circumscissa_ (_Wallr._) of Rostafinski's monograph; but it is doubtful to what Wallroth referred. Rostafinski's other citations are equally uncertain. Currey's figures and description alone merit recognition.

Ohio, Iowa, Tennessee; Canada.

3. OPHIOTHECA WRIGHTII _Berk._

PLATE II., Figs. 7, 7 _a_, 7 _b_.

1868. _Ophiotheca wrightii_ Berk. & C., _Jour. Linn. Soc._, X.,
p. 349.
1876. _Cornuvia wrightii_ (Berk. & C.) Rost., _Mon. App._, p. 36.
1892. _Cornuvia wrightii_ (Berk. & C.) Macbr., _Bull. Lab. Nat.
Hist. Ia._, II., p. 122.
1911. _Perichaena chrysosperma_ Lister, _Mycetozoa, 2nd ed._,
p. 248.

Plasmodiocarp bent or short-flexuous, often arcuate or completely annular, dark chestnut brown or black, opening irregularly; peridium thin, brittle, translucent, covered without by a rather dense layer of brownish or black brown scales; capillitium of long, sparingly branched threads furnished with projecting spinules remarkable for their length, about twice the diameter of the thread; spores yellow, minutely but distinctly warted, about 12 mu.

This is the common species everywhere on the inner side of the bark of fallen trees, _Ulmus_, etc. It is readily distinguished at sight by the peculiar annular, looped, and U-shaped plasmodiocarps, with their dark umbrine or blackened surface. From the preceding it is especially distinguished by the spinulose capillitium and larger spores.

Not rare. New England, New York, Pennsylvania, Ohio.

=2. Perichaena= _Fries_

1817. _Perichaena_ Fries, _Symb. Gast._, p. 11.

Sporangia flattened, sometimes small and roundish, more often larger, polygonal by mutual interference, or irregular, the peridium thickened outwardly by a dense reddish or brownish layer of scales; dehiscing by circumscission or by a lid; capillitium often scant, of slender, warted, yellowish threads, attached betimes to the upper wall; spores yellow, oval or spherical.

=Key to the Species of Perichaena=

_A._ Sporangia plainly flattened.

_a._ Very flat, sporangia 1mm. or more in width 1. _P. depressa_

_b._ Depressed; sporangia smaller 2. _P. quadrata_

_B._ Sporangia more or less spherical

_a._ Chestnut brown 3. _P. corticalis_

_b._ Gray or canescent 4. _P. marginata_

1. PERICHAENA DEPRESSA _Libert._

PLATE XVII., Fig. 10.

1837. _Perichaena depressa_ Lib., _Fl. Crypt. Ard._, IV., No., 378.

Sporangia sessile, applanate, crowded, polygonal by mutual contact, fuscous or chestnut brown, shining, opening by a definite lid; spore-mass and capillitium yellow, the capillitium well developed, of slender yellow threads of various widths, almost smooth; spores minutely warted, 10-12 mu.

Easily recognized by the peculiar, polygonal, depressed-flattened sporangia and consequent shallow spore-cases in which lie the yellow spores and scanty capillitium. Rostafinski refers here _P. vaporaria_ Schw., No. 2311, but the meagre description seems rather to apply to the next species. The original material is no longer accessible.

In the crevices and on the inside of bark of fallen logs of various sorts, walnut, maple, etc.

Not commonly collected. Specimens are before us from New England, Illinois, Iowa, Missouri, Florida, Mexico, Nicaragua. Probably over the whole wooded region of the continent.

2. PERICHAENA QUADRATA _Macbr._

1893. _Perichaena irregularis_ Berk. & C., Morgan, _Jour. Cin. Soc._,
p. 20.

Sporangia very small, less than 1/2 mm., crowded, polygonal or quadrangular, depressed, but not flattened, smooth, bright rufous or brown; the peridium rather thick, yellow within, the dehiscence circumscissile; capillitium scanty, of slender, sparingly branched filaments, the surface minutely roughened, warted or spinulose; spore-mass yellow; by transmitted light pale yellow, 9-11 mu.

Differs from the preceding by the much smaller size of the sporangia, different color and habit. The sporangia, while depressed, still maintain considerable rotundity; they are occasionally quite spherical, and then of very uneven size, hardly in contact. In some cases the plasmodium before maturing seems to assume the form of a plasmodiocarp, which, by transverse fission at intervals, forms the curious four-sided conceptacles. At other times the plasmodium assumes the shape of a flat cushion or plate, which then subdivides into minute polygonal segments. This form has been known some years to collectors, and, if named at all, has been called _P. irregularis_. Lister, _l. c._, assures us that Berkeley's type "is typical _P. depressa_."

Not common. Pennsylvania, Ohio, Illinois, Missouri.

3. PERICHAENA CORTICALIS (_Batsch_) _Rost._

PLATE II., Figs. 1, 1 _a_, 1 _b_.

1783. _Lycoperdon corticale_ Batsch, _Elench. Fung._, p. 155.
1875. _Perichaena corticalis_ (Batsch) Rost., _Mon._, p. 293.
1817. _Perichaena populina_ Fries, _Symb. Gast._, p. 12.

Sporangia sessile, gregarious, flattened, hemispherical; peridia simple, opening by a lid; dehiscence circumscissile, the upper part chestnut brown, the lower almost black; capillitium feebly developed, smooth, attached to the lid and usually coming away with it, bringing the brilliantly yellow spore-mass, and leaving a delicate, shining cupule adherent to the substratum; spores yellow, nearly smooth, 10-12 mu. On and under the bark of dead elms of various species.

A very handsome little species occuring rarely with us, or perhaps overlooked by virtue of its protective coloration. Found sometimes on the inner side of the bark where the latter has separated, but not yet wholly parted company with the wood. In such situations the tiny sporangia are so nearly quite the color of the moist substratum as to escape all but the closest scrutiny. The dehiscence is very remarkable, characteristic, beautiful. Black, brown, chestnut, and gold are harmoniously blended, in the opening coffers. Prior to maturity the future line of fission is plainly indicated by the difference in color.

This is clearly the species found by Batsch "ligni demortui putridi in interiore corticis pagina." Bulliard has also described and figured the species, _Sphaerocarpus sessilis_ t. 417, Fig. V.

The capillitium is nearly smooth; the spores are only slightly roughened by minute warts.

Apparently not common. Iowa, Missouri; Black Hills, South Dakota; Canada;--_Miss Currie._

4. PERICHAENA MARGINATA _Schweinitz._

1831. _Perichaena marginata_ Schw., _N. A. F._, No. 2319, p. 258.

Sporangia depressed, globose, polygonal as they become approximate or crowded, hoary canescent, sessile; peridium rather thick, persistent, circumscissile in dehiscence, covered without by minute whitish calcareous (?) scales, within punctate by the imprint of the spores; hypothallus distinct, white; capillitium scant or none! Spores in mass dull yellow, by transmitted light pale, nearly smooth, 14-15 mu.

Lister, following Rostafinski, includes this form with the preceding. The differences between the two forms are, it seems to us, sufficient to make convenient their separation as by Schweinitz. Apart from the peculiar incrustation in the present species, the larger spores, and especially the peculiar white hypothallus, are distinctive. The method of dehiscence is also different. In _P. corticalis_ the line of cleavage before spore dispersal is indicated by a definite band surrounding the sporangium. Nothing similar appears in the gray specimens of the present form, although the dehiscence is quite as certainly circumscissile. The habitat in American specimens is the _outer_ surface of the bark, which causes the species generally, by protective coloration, to be overlooked.

Not common. Pennsylvania, Ohio, Missouri.

_C._ ARCYRIACEAE

=Key to the Genera of the Arcyriaceae=

_A._ Peridium becoming fragmentary, but persisting;
capillitium non-elastic 1. LACHNOBOLUS

_B._ Peridium evanescent above, persistent below;
capillitium elastic 2. ARCYRIA

_C._ Capillitium elastic, bearing hamate branches 3. HETEROTRICHIA

=1. Lachnobolus= _Fries_.

1829. _Lachnobolus_ Fries, _Syst. Myc._, III., p. 177.

Sporangia distinct, sessile or nearly so, globose or cylindric, often distorted, scattered or densely crowded, the peridium extremely thin, ruptured irregularly, and persistent in fragments; capillitium attached at numerous points to the sporangial wall, forming a dense net, the threads warted or spinulose, non-elastic.

Species of this genus are easily distinguished from those of the next by the peculiar fragile peridium and the inelastic capillitium.

=Key to the Species of Lachnobolus=

_A._ Sporangia pale yellow, on fallen flowers and
fruit-burs of Castanea 1. _L. globosus_

_B._ Sporangia rosy or copper-colored, at length
ochraceous 2. _L. occidentalis_

1. LACHNOBOLUS GLOBOSUS (_Schw._) _Rost._

1822. _Arcyria globosa_ Schw., _Syn. Fung. Carol._, No. 400.
1875. Lachnobolus globosus (Schw.) _Rost., Mon._, p. 283.
1894. _Arcyria albida_ Pers. (in part) Lister, _Mycetozoa_, p. 186.

Sporangia on the spines of fallen chestnut burs, scattered, pale yellow or whitish, small, globose, the peridium early evanescent above, more persistent below, stipitate; stipe small, tapering upward, from a small hypothallus; capillitium a dense but not expanding network attached chiefly to the lower portion of the sporangial wall, minutely waited or roughened, with few expansions or inflations; spores in mass pale yellow, under the lens colorless, almost smooth, 7-8 mu.

This singular little species is remarkable chiefly in the habitat it affects,--fallen chestnut burs. On these almost universal, but on nothing else, except on the fallen catkins of the same species. Regarded by Mr. Lister as _A. cinerea_, from which it differs constantly in form, in capillitium more open and with larger threads, 4-5 mu in diameter as well as in its unique habitat, and yellowish color.

Distribution coterminous with that of _Castanea dentata_ Borkhausen,--eastern half of the United States.

2. LACHNOBOLUS OCCIDENTALIS _Macbr._

PLATE II., Figs. 2, 2 _a_, 2 _b_; 4 and 4 _a_.

1885. _Lachnobolus incarnatus_ (Alb. & Schw.) Macbr., _Bull. Lab.
Nat. Hist. Iowa_, II., p. 126.

Sporangia scattered or crowded upon a hypothallus more or less distinct, globose or ellipsoidal, short-stipitate, varying somewhat in color, at first rosy or flesh-colored, later brownish or ochraceous; the peridium exceedingly thin, pellucid, mealy, evanescent above, persisting as a shallow cup below; capillitium inelastic, rather closely netted of threads variable in thickness, marked by frequent thickenings or expansions, everywhere warted, attached to the peridial walls, spores in mass flesh-colored, under the lens colorless, smooth, globose, 7.5-9 mu.

This delicate and elegant little species appears to be not uncommon, but is probably generally passed over as an _Arcyria_, which it superficially resembles. When newly formed, the sporangia have a peculiar rosy or flesh-colored metallic tint, which is all their own. Within a short time this color passes, and most of the material comes from the field brownish or ochraceous in color. Typical sporangia are spherical on distinct short stipes; when crowded, the shape is of course less definite. The capillitium never expands as in _Arcyria_, but, exposed by the vanishing upper wall, remains a spherical mass resting upon the shallow cup-like base of the peridium.

This species has been in the United States generally distributed as _L. incarnatus_ (Alb. & Schw.) Schroet. A careful study of all descriptions of European forms and comparison of many specimens leads us to believe that we have here to do with a type presenting constant peculiarities. We have in America nothing to correspond with the figures of Schweinitz, Berkeley, or Lister. In the American gatherings the sporangia are uniformly regular, globose, very generally short-stipitate, more or less closely gregarious, never superimposed, or heaped as shown in Berkeley's figure, for instance, _Ann. and Mag. Nat. Hist._, IV., xvii., Pl. ix., Fig. 2. The plasmodium of our species is white; as it approaches maturity a rosy metallic tinge supervenes, quickly changing to dull yellow or alutaceous. The graphic description given by Fries of _Perichaena incarnata_, _Syst. Myc._, III., p. 193, presents scarcely a character attributable to the form before us. _L. congesta_ Berk. & Br., evidently the form figured and described by Lister, _Mycetozoa_, p. 194, Pl. lxx., B., resembles our species in color and capillitium, but is entirely different in habit.

Not uncommon. Maine, Iowa, Missouri, Nebraska.

=2. Arcyria= (_Hill_) _Pers._

1751. _Arcyria_ Sir John Hill, _Gen. Nat. Hist._, II., p. 47.
1801. _Arcyria_ Pers., _Syn. Fung._, p. 182.

Sporangia ovoid or cylindric or even globose, stipitate; the peridium thin, evanescent to near the base, the lower part persisting as a calyculus; the stipe variable, packed with free cell-like vesicles, resembling spores, but larger; capillitium attached below, to the interior of the stipe or to the calyculus, in form an elastic network, the tubules adorned with warts, spinules, half-rings, etc., but without spiral bands or free extremities.

Micheli, of course, discovered the arcyrias, put them in two genera and several species, which we may only dimly recognize. Persoon first saw distinctly the outlines of the genus as now understood and adopted the name given by Hill in his curiously prolix description of certain species, probably partly of the genus _Arcyria_, partly _Stemonitis_.

=Key to the Species of Arcyria=

_A._ Mature capillitium loosely adhering to the calyculus.

_a._ Mature capillitium far-expanded, drooping.

i. Dusky.

O Long, 12 mm. or more 1. _A. magna_

OO Shorter, about 6 mm. 2. _A. oerstedtii_

ii. Yellow 3. _A. nutans_

_b._ Mature capillitium short, not drooping, though
sometimes procumbent.

i. Capillitium greenish yellow 4. _A. versicolor_

ii. Capillitium reddish, flesh-colored, at
length sordid, etc.

O Capillitium marked by transverse
half-rings, cogs, etc. 5. _A. incarnata_

OO Capillitium marked by sharp-edged
transverse plates and by numerous
nodes 6. _A. nodulosa_

OOO Capillitium marked by close
reticulations 7. _A. ferruginea_

_B._ Capillitium persistently attached to the calyculus.

_a._ Sporangia reddish brown, etc. 8. _A. denudata_

_b._ Sporangia gray or ashen

i. Simple 9. _A. cinerea_

ii. Clustered 10. _A. digitata_

_c._ Sporangia yellow 11. _A. pomiformis_

_d._ Sporangia rose-colored, .5-1.5 mm. 12. _A. insignis_

1. ARCYRIA MAGNA _Rex._

1893. _Arcyria magna_ Rex, _Proc. Phil. Acad._, p. 364.

Sporangia densely aggregated, forming clusters of greater or less extent, sometimes reaching several centimetres in either direction, tawny gray or ashen, cylindric, tapering a little above, when expanded reaching a length of half a centimetre or more, stipitate; peridium evanescent except the small shallow cup-like base, the calyculus; stipe long (1 mm.), weak, pale brown or reddish, tubular, the channel filled with plasmodic masses; capillitium gray or drab-colored, very slightly attached to the bottom of the calyculus, far expanded, forming a loose-meshed net, the threads regular, cylindric, coarsely sculptured with rings, half-rings, cogs, spines, etc.; spores in mass dull gray, drab, under the lens colorless, papillate, with few papillae, 7-8 mu.

This magnificent form resembles in habit and general appearance, save color, _A. nutans_. The capillitium is, however, very different both in the sculpture and in the more delicate markings of the threads. Dr. Rex, _l. c._, has pointed out the lack of reticulation on the capillitium and calyculus. The color is also diagnostic. A roseate variety seems to occur with the present form. This is _A. magna rosea_ Rex, and appears to agree with the type in all respects save color. The relationship here must be determined by future inquiry. The capillitial threads are remarkable for their graceful slenderness, regularity, and symmetry.

2. ARCYRIA OERSTEDTII _Rost._

1875. _Arcyria oerstedtii_ Rost., _Mon._, p. 278, Fig. 196.

Sporangia cylindric, arcuate, 1.5 mm. high when unexpanded, closely clustered, dull crimson, stipitate; peridium evanescent except here and there a persistent patch, the calyculus shallow, plicate, papillose within; stipe short, weak, concolorous; hypothallus distinct, membranous, concolorous; capillitium a loose, far-expanding, elastic net, the meshes uneven, often small, the threads characterized by much irregularity and many bulbose thickenings, especially at the nodes, strongly spinulose throughout; spore-mass crimson or reddish brown, dull; spores by transmitted light colorless, nearly smooth, sub-globose, 9-10 mu.

This well-marked species is certainly rare within our limits. We have specimens from New England and from Pennsylvania. The Iowa material referred to this species, _Bull. Lab. Nat. Hist. Ia._, II., p. 125, is _A. magna_ Rex. Rostafinski's figure is excellent in the present case, and gives the idea of what we regard the typical marking of the capillitium in _A. oerstedtii_. Externally the species resembles somewhat _A. nodulosa_, and the network of the capillitium is also suggestive of that form; the spiny capillitium is unique.

Rare. Adirondacks, New York--_Dr. Rex._

3. ARCYRIA NUTANS (_Bull._) _Grev._

PLATE II., Figs. 6, 6 _a_, 6 _b_.

1791. _Trichia nutans_ Bulliard, _Champ._, p. 122, t. 502, III.
1794. _Arcyria flava_ Pers., _Roemer N. Mag. Bot._, I., p. 90.
1824. _Arcyria nutans_ Grev., _Fl. Edin._, p. 455.

Sporangia crowded, cylindric, about 2 mm. high when unexpanded, pale yellow or buff, short-stipitate or sessile by an acute base; peridium wholly evanescent, except at the base, where persists the shallow, colorless, often inwardly spinulose, plicatulate calyculus; stipe very short or wanting; hypothallus thin but usually in evidence; capillitium expanding to great length, forming an extremely flexile, plumose, pendulose open network of pale ochraceous tint, the threads 3-4 mu in thickness, adorned with spinules, sharp edged transverse plates sometimes rings, the surface especially marked by an indistinct reticulation; spore-mass buff or ochraceous, spores by transmitted light colorless, smooth or nearly so, 7-8 mu.

This elegant species is not rare in undisturbed woods, especially on fallen willows. The expanded capillitia are very soft and plume-like, waving and nodding, very lightly attached below to the centre of the peridial cup. The capillitium threads are rough, with irregular spines and sharp-edged transverse plates, occasionally extending to form rings. Resembles the first species somewhat in habit, size, and the spinescent capillitium, but the resemblance is superficial only. The color is at once diagnostic, and the capillitium is after all entirely different. Not uncommon; Canada to Mexico; Maine to California; probably cosmopolitan.

Bulliard's figure determines the synonymy. Persoon called the form _A. flava_, because Bulliard had missed the genus.

4. ARCYRIA VERSICOLOR _Phillips._

1877. _Arcyria versicolor_ Phillips, _Grev._, V., p. 115.
1877. _Arcyria vitellina_ Phillips, _Grev._, V., p. 115.

Sporangia gregarious or more or less crowded, pyriform or clavate, dingy, olivaceous yellow, becoming reddish, stipitate; peridium membranous, largely persistent below, where it gives rise to the deep, goblet-shaped calyculus; stipe strand-like, weak, sometimes wanting, concolorous with the peridium; hypothallus prominent or venulose; capillitium only slowly expanded, bright golden yellow or orange, the threads rather broad, about 4 mu in diameter, regular, even, elegantly branching, adorned with abundant short spines or warts, very small and evenly distributed, the whole net anchored in the bottom of the vasiform calyculus; spore-mass yellow, by transmitted light pale or nearly colorless, smooth, about 10 mu.

This beautiful species is easily known by its comparatively large size, peculiar, obovate shape, its brilliant color, and unusually persistent membranous calyculus. It is peculiar to the western part of North America, South Dakota west to the Pacific Ocean.

South Dakota, Colorado, California, Washington.

In the thin-covered mountains of Colorado, or hidden by the still drier thickets and woods of Southern California, the fruit of this species is small, somewhat as the clavate hemitrichia, pure, deep yellow, golden or vitelline as Phillips says; but at loftier altitudes in the ever cool forests on the high mountain flanks, beginning away up where the glacier first starts to crack and slide between the 'cleavers', and forests of stunted white-stemmed pine or wooly-fruited fir throw down their twigs and foliage undisturbed through centuries,--on down to where the plowing ice forgets its thrust, and melts to gentle floods amid spruce and hemlock-groves,--all the way the beautiful versicolor spreads and fruits, in August and September in all the richness of color which its name implies, which Phillips saw, tints of red, and yellow, and olive, and green, not brilliant, but in all the softer shades the artists love, weaving, in far-spread strands of tufted cylinders and cones upturned, fair as flowers, dusky garlands, by sunlight long forgot! Did not the old-time botanists liken these things once and again, to flowers!

5. ARCYRIA INCARNATA _Persoon._

1786. _Clathrus adnatus_ Batsch, _Elench. Fung._, 141. (?)
1791. _Arcyria incarnata_ Pers., Gmel., _Syst. Nat._, II., 1467.

Sporangia closely crowded, cylindric, 1-1.5 mm. high, rosy or flesh-colored, stipitate or almost sessile; stipe generally short, sometimes barely a conical point beneath the calyculus; hypothallus none; peridium wholly evanescent, except the shallow, saucer-like, inwardly roughened calyculus; capillitium loose, broad, pale reddish, attached to the cup at the centre only by strands which enter the hollow stem, the threads adorned with transverse plates, cogs, ridges, etc., arranged in an open spiral; spore-mass rosy, spores by transmitted light colorless, nearly smooth, 7-8 mu.

This common species is well marked both by its color and by the delicate attachment of the capillitium to the calyculus. This is so frail that the slightest breath ofttimes suffices to effect a separation, and the empty calyculi are not infrequently the only evidence of the fructification. This peculiarity did not escape the attention of Persoon, and is well shown in his figure (_Obs. Myc._, I., p. 58, pl. V. Figs. 4 and 5) referred to by Gmelin, _l. c._ Batsch simply named and described Micheli's figure (Tab. XCIV., Fig. 2), and accordingly his claim to priority is no better than Micheli's figure, which may possibly concern the present species, but is in no sense determinative. It is impossible to say what Retzius meant by his _Clathrus ramosus_, cited by Fries as a synonym here.

Common, especially in the Mississippi valley and south; more rare in the west; Black Hills, South Dakota; Toronto to New Mexico.

6. ARCYRIA NODULOSA _Macbr._

PLATE III., Fig. 8.

Sporangia small, about 1 mm. high when unexpanded, crowded in clusters of varying size, dull red or brownish, stipitate; the peridium evanescent except the cup; stipe very short, concolorous, plicate as the cup, or both smooth and unmarked; capillitium centrally attached, slowly expanded, open-meshed, dense, the threads even, 5-6 mu wide, expanded in globose, spinulose, or papillate-reticulate nodules, especially at points of intersection, marked everywhere by close-set, transverse, sharp-edged ridges, which encircle the thread and show no trace of spiral arrangement; spore-mass brown or red brown; spores by transmitted light pale yellow or colorless, minutely but distinctly roughened, globose, 10-12 mu.

This variety is not distantly related to the preceding, as shown by the centrally attached capillitial mass, but differs in several definite particulars; the sporangia are much smaller of an entirely different color with longer stipes, larger, rougher spores; the capillitium is also peculiar, the threads unusually wide and densely corrugated transversely, expanding at frequent intervals into globose nodules which are sometimes double the width of the thread. In color suggests _A. affinis_ Rost., but corresponds to no other particular.

7. ARCYRIA FERRUGINEA _Sauter._

PLATE XII., Figs. 6, 6 _a_, 6 _b_.

1841. _Arcyria ferruginea_ Saut., _Flora_, XXIV., p. 316.
1881. _Arcyria macrospora_ Peck, _Rep. N. Y. Mus._, XXXIV., p. 43.
1883. _Arcyria aurantiaca_ Raunier, _Myx. Dan._, p. (44).

Sporangia ovoid or short cylindric, crowded or gregarious, dull red or brownish, stipitate; stipe about equal to the sporangium, dark brown or black; hypothallus well developed, membranous, yellowish brown continuous; calyculus large, wide and shallow, smooth; capillitium centrally attached, when fresh, brick-red in color, fading on exposure, the threads of uneven size, those above 6-7 mu, below 3 mu, abundantly branching, marked by conspicuous reticulations formed by the intersection of numerous vertical plates or ridges; spore-mass reddish, spores by transmitted light pale ochraceous, distinctly warted, 10-12 mu.

This species is distinguishable at sight by the peculiar color and form of the sporangia. Mr. Durand in _Bot. Gaz._, XIX., pp 89, 90, gives a careful study of the form. The same author declares the dehiscence circumscissile. We cannot distinguish _A. aurantiaca_ Raun. from the present form.

Rare. Maine, New York; Monterey, California.

8. ARCYRIA DENUDATA (_Linn._) _Sheldon._

PLATE II., Figs. 5, 5 _a_.

1753. _Clathrus denudatus_ Linn., _Syst. Nat._, 1179.
1794. _Arcyria punicea_ Pers., _Roem. N. Mag. Bot._, I., p. 90.
1895. _Arcyria denudata_ (Linn.) Sheld., _Minn. Bot. Studies_,
No. 9, p. 470.

Sporangia crowded or gregarious, ovoid or short cylindrical, tapering upward, red-brown, stipitate; peridium evanescent except the plicate calyculus; stipe about equal to the expanded capillitium, concolorous, plicate or striate, ascending from a small hypothallus; capillitium attached to the whole inner surface of the calyculus and connate with it; hence not deciduous, bright red or carmine when fresh, turning brown or paler with age, the threads even, about 3 mu adorned with a series of rather distant cogs or half rings, which form around the thread a lengthened spiral; spore-mass red or reddish brown, spores by transmitted light colorless, nearly smooth, 6-8 mu.

This species is easily distinguished from all other of similar tints by the attachment of the capillitium. In this respect it corresponds with the following species. In the adornment of the threads it is like _A. incarnata_. It is by far the commonest species of the genus, and probably enjoys a world-wide distribution. To be found at all seasons on the lower side of fallen sticks, _Populus_, _Tilia_, etc.

Micheli, Pl. XCIV., shows that he had the present species. The description given by Linne is worthless, but helped out by Micheli, and several other authors of the eighteenth century, who take the trouble to describe the species, but still give the Linnean binomial as a synonym; we may give Linne here the credit. As a matter of fact, Batsch under _Embolus crocatus_ first presents an unmistakable description and figure.

Maine to the Black Hills and Colorado, and north and west; Alaska to Nicaragua.

9. ARCYRIA CINEREA (_Bull._) _Pers._

PLATE II., Figs. 3, 3 _a_.

1791. _Trichia cinerea_ Bull., _Champ. de France_, p. 120, Tab. 477,
Fig. iii.
1801. _Arcyria cinerea_ (Bull.) Pers., _Syn. Fung._, p. 184.

Sporangia scattered or gregarious, ovoid or cylindrical, generally tapering upward, about 2-3 mm. high, ashen gray, sometimes with a yellowish tinge, stipitate; calyculus very small, thin; stipe about half the total height, rising from a small hypothallus, thin, gray or blackish, densely crowded with spore-like cells; capillitium dense, freely branching, ashen, or yellowish, little wider below, minutely spinulose; spore-mass concolorous, spores by transmitted light colorless, smooth, 6-7 mu.

A very common little species, easily recognized by its color and habit. The capillitium is more dense than in any other species and expands less. The stipe is about equal to the expanded capillitium, unusually long. The plasmodium occurs in rotten wood, especially species of _Tilia_, is gray and, judging from the number of sporangia found in one place, scanty.

Bulliard, _l. c._, gives the first account of the species by which it can with any certainty be identified. By some authors _Clathrus recutitus_ Linn. is cited as a synonym. We fail to distinguish _A. cookei_ Mass. from the old type.

Widely distributed; Maine to Alaska, and south to Mexico and Nicaragua.

10. ARCYRIA DIGITATA (_Schw._) _Rost._

1831. _Stemonitis digitata_ Schw., _N. A. F._, p. 260, No. 2350.
1868. _Arcyria bicolor_ Berk. & C., _Jour. Linn. Soc._, X., p. 349.
1875. _Arcyria digitata_ (Schw.) Rost., _Mon._, p. 274.

Sporangia compound, that is gathered in tufts, number 3-12 or more on a single stipe, the clusters themselves scattered; individual sporangia elongate cylindric, about 3-4 mm. long, ashen gray or nearly white, stipitate; stipe as long or longer than the sporangium, stout, sometimes showing traces of consolidation of several, sometimes none, dark brown or black; capillitium looser and more expanded than in the last, the threads more strongly spinulose; spore-mass concolorous, spores under the lens colorless, smooth, globose, 7.5-8 mu

Closely related to the preceding, but different in habit and on the whole larger and more robust throughout. The stipes in some cases are completely merged in one; in others traces of coalescence remain. The number of united sporangia varies. There are some clusters before us containing 16 and 18 in a single fascicle!

Not very common. On rotten wood of deciduous trees, especially south.

New England, Pennsylvania, Ohio; Black Hills, South Dakota, and south to Nicaragua.

_Arcyria bicolor_ Berk. & C. seems to refer to the fact that the sporangia have sometimes an ochraceous tint. Berkeley's specimens are from Cuba. Our latest specimens are from Nicaragua; the form seems not to be reported from the old world.

11. ARCYRIA POMIFORMIS (_Leers_) _Rost._

1775. _Mucor pomiformis_ Leers, _Flor. Herb._, p. 218.
1875. _Arcyria pomiformis_ Rost., _Mon._, p. 271.

Sporangia scattered, gregarious, globose, bright yellow, very minute, .5 mm. high, .3 mm. in diameter, stipitate; stipe short, one-third the total height, pale brown or yellow; hypothallus none; capillitium loose, freely expanding, not deciduous, honey-yellow, the threads generally wide, 4-5 mu, toward the periphery more narrow, 2.5 mu warted, marked with blunt spinules, which not infrequently pass into distinct transverse, narrow plates or half-rings, free ends clavate and numerous; spore-mass yellow, spores by transmitted light smooth, granular, globose, 7-9 mu.

This species as represented by the material before us seems constant in size, color, and microscopic characters, in all which it differs from all species here listed. It resembles somewhat _Lachnobolus globosus_ Schw., but differs in habit, habitat, color, the capillitium, its attachment and in the mode of dehiscence. In the present species the wall is evanescent almost _in toto_; in _L. globosus_ is it remarkably persistent, and the capillitium is adherent.

Probably rare. Its smallness removes it from sight of all but the most exact collectors. Maine, New York, South Carolina, Alabama, Missouri, Iowa; Black Hills, South Dakota; Ontario;--_Miss Currie._

While usually remotely gregarious a collection from southern California shows that on occasion the entire plasmodium may pass to fruit with narrowest limits, forming a stipitate, compact, globose mass of crowded, superimposed sporangia as in _Oligonema nitens_. Set Plate XX., Fig. 12.

12. ARCYRIA INSIGNIS _Kalkbr. & Cke._

1882. _Arcyria insignis_ Kalkbr. & Cke., _Grev._, X., p. 143.
1911. _Arcyria insignis_ Kalkbr. & Cke., List., _Mycet., 2nd ed._,
p. 240.

Sporangia gregarious or clustered, pale or bright rose-colored, .5-1.5 mm. in height, stipitate, ovate or cylindric; stipe short, .2-.4 mm. red, with spore-like cells; capillitium a close net-work of delicate threads with a few bulbous free ends, with faint transverse bands or short spinules, or nearly smooth, colorless beneath the lens; spores colorless, nearly smooth, 6-8 mu.

Reported from Mass. by Miss Lister. Should follow No. 8: apparently a very delicate form of the common species, _A. denudata_.

=3. Heterotrichia= _Mass._

1892. _Heterotrichia_ Mass., _Mon._, p. 139.

Sporangia distinct, stipitate; the peridium simple evanescent above as in _Arcyria_; capillitium centrally attached, freely branched, the threads within very slender, without broad, anastomosing to form a dense peripheral network, and everywhere extended to form short, free, often hamate tips. A single species,--

1. HETEROTRICHIA GABRIELLAE (_Rav._) _Mass._

PLATE XIII., Figs. 1, 1 _a._

1850. _Arcyria gabriellae_ Rav. _in litt. ad Cooke_.
1892. _Heterotrichia gabriellae_ Mass., _Mon._, p. 140.
1911. _Arcyria ferruginea_ Saut., var. _heterotrichia_ List., _Mycet.,
2nd ed._, p. 234.

Sporangia crowded or gregarious, oblong cylindric, ovoid, at first red, becoming yellowish brown, stipitate; the peridium evanscent except the calyculus, which is small and thin, polished; stipe shorter than the expanded capillitium, pale reddish brown; capillitium centrally attached, showing threads of two sorts, those within freely branching, slender, 1-1.5 mu, marked with half-rings or ridges, those on the periphery very different, yellow, broad, 5-6 mu, forming rather dense reticulations, with abundant free tips, acute and often curved, the whole surface here minutely and densely warted; spore-mass reddish yellow, spores by transmitted light colorless, globose, 7-8 mu.

The peculiar double capillitium seems to separate this form from the true arcyrias. Some difference in the diameter of the capillitial threads in different regions is not infrequent in the several species of _Arcyria_, but that difference is here emphasized and rendered yet more striking by the peculiar free tips. The present forms bear only the most superficial resemblance to _A. ferruginea_ Saut., with which species it is in some quarters sought to unite it.

Very rare. Collected, as noted, nearly fifty years ago in South Carolina by Ravenel, it was more recently (1896) again collected in Maine by the late Professor Harvey.

_D._ PROTOTRICHIACAE

A single genus,--

=Prototrichia= _Rost._

1876. _Prototrichia_ Rost., _Mon. App._, p. 38.

A single species,--

1. PROTOTRICHIA METALLICA (_Berk._) _Mass._

PLATE XVIII., Figs. 12, 12 _a_, 12 _b_.

1860. _Trichia metallica_ Berk. Hook., _Fl. Tasm._, 2, p. 168.
1866. _Trichia flagellifera_ Berk. & Br., _Ann. Mag. Nat. Hist._, 3,
XVII., p. 56.
1876. _Prototrichia flagellifera_ (Berk.) Rost. _Mon. App._, p. 38.
1894. _Prototrichia flagellifera_ Rost., List., _Mycet. 2nd ed._,
p. 206.
1899. _Prototrichia flagellifera_ (Berk. & Br.) Rost., Macbr.,
_N. A. S._, p. 199.
1892. _Prototrichia metallica_ Mass., _Mon._, p. 127.
1911. _Prototrichia metallica_ Mass., List., _Mycet., 2nd ed._,
p. 260.

Sporangia sessile, scattered or sometimes crowded, brown, sometimes with a rosy tinge, about 1 mm. in diameter; peridium a thin, transparent, iridescent membrane, bearing in its inner surface the distal attachments of the capillitial threads; capillitium of numerous brown, spirally banded threads, which take origin in the base of the sporangium, become subdivided as they ascend, and are at length attached by their tips to the sporangium wall; spore-mass brown, spores by transmitted light pale, minutely roughened.

This curious form, with its spirally sculptured capillitial threads attached at both ends, stands intermediate between _Dianema_ and _Hemitrichia_ and _Trichia_. Berkeley called it a trichia, ignoring the attachment of the threads. Cooke notes this as sufficient to exclude the form from the genus. But it remained for Rostafinski to make the transfer by setting up for its reception the genus now adopted. He preferred the later (1866) specific name as more descriptive. Miss Lister reverts to the earlier name with the remark; "Little now remains of the type _Prototrichia metallica_ Berk. from Tasmania; but the specimen is referred to _Prototrichia flagellifera_ by Rostafinski who saw it in good condition."

Not uncommon in the abietine forests of the West. Alberta, Oregon, Washington, California, Nevada, Montana, Idaho, Colorado.

_E._ TRICHIACEAE

Capillitium marked by spiral bands, sometimes scattered rings, etc., the threads entirely free, or at least loosely branched, and with free tips more or less numerous.

=Key to the Genera of the Trichiaceae=

_A._ Capillitium threads long, generally united to
form a loose net, centrally attached.

_a._ Sculpture spiral 1. _Hemitrichia_

_b._ Sculpture reticulate 2. _Calonema_

_B._ Capillitial threads shorter, entirely free,
though sometimes branched.

_a._ Threads, elaters, marked by spiral bands 3. _Trichia_

_b._ Sculpture irregular or wanting 4. _Oligonema_

=1. Hemitrichia= _Rost._

1829. _Hemiarcyria_ Fries, _Syst. Myc._, III., p. 183 in part.
1873. _Hemitrichia_ Rost., _Versuch_, p. 14.

Capillitium a tangled net of more or less branching and anastomosing fibres centrally attached; the sculpture regular, of conspicuous spirally winding bands or ridges; habit and color various.

The species here associated are intermediate between _Arcyria_ and _Trichia_, resembling the former in the capillitial net and the latter in thread-sculpture. Fries applied the name _Hemiarcyrieae_ to a group of trichias so-called, citing _H. rubiformis_ as the first. In his _Versuch_ Rostafinski wrote _Hemitrichia_ and afterward _Hemiarcyria_ in the _Monograph_. Massee combines the genera _Arcyria_ and _Hemiarcyria_ under the former name.

=Key to the Species of Hemitrichia=

_A._ Plasmodiocarpous

_a._ Plasmodiocarp net-like, yellow 1. _H. serpula_

_b._ Imperfectly plasmodiocarpous, brown 2. _H. karstenii_

_B._ Sporangia all distinct.

_a._ Sessile; very short stalked

i. Peridium hyaline, iridescent 3. _H. ovata_

ii. Peridium opaque 10. _H. montana_

_b._ Stipitate, generally distinctly so; sometimes
nearly sessile.

i. Yellow or ochraceous.

O Stalk hollow.

+ Small, 1/2 mm., iridescent 6. _H. leiocarpa_

++ Larger, 1 mm., smooth but not iridescent

1. Free ends more or less abundant 8. _H. clavata_

2. Free ends none 9. _H. stipitata_

OO Stalk solid 7. _H. intorta_

ii. Not yellow.

O Ruby red 4. _H. vesparium_

OO Copper-colored 5. _H. stipata_

1. HEMITRICHIA SERPULA (_Scop._) _Rost._

PLATE III., Figs. 4, 4 _a_, 4 _b_.

1772. _Mucor serpula_ Scop., _Fl. Carn_, II., p. 493.
1794. _Trichia serpula_ (Scop.) Pers., _Roem. N. Bot. Mag._, I., p. 90
1875. _Hemiarcyria serpula_ (Scop.) Rost., _Mon._, p. 266.

Fructification plasmodiocarpous, often covering several square centimetres, terete, branching freely and usually everywhere reticulate, rusty, tawny, or bright yellow; the peridium thin, transparent, with irregular dehiscence; hypothallus none; capillitium variable, a tangle of long yellow threads, sparingly branched, free everywhere, except below, spinulose, the free tips spinose, acuminate, spiral ridges three or four, with traces of longitudinal striae; spore-mass golden yellow, spores beneath the lens pale yellow, globose, delicately reticulate, about 10 mu.

Very common, recognized by its bright yellow color and conspicuous reticulate habit. The plasmodium is yellow, at least upon emergence, and passes almost without change to fruit. Found on rotten logs of every description, on the _lower_ surface. In the Mississippi valley, the lower surface of planks used in the construction of sidewalks appears to be a favorite habitat.

Common west to the Rocky Mountains, south to Mexico and Nicaragua.

2. HEMITRICHIA KARSTENII (_Rost._) _List._

1876. _Hemiarcyria karstenii_ Rost., _Mon., App._, p. 41.
1891. _Hemiarcyria obscura_ Rex, _Proc. Phil. Acad._, p. 395.
1894. _Hemitrichia karstenii_ Lister, _Mycetozoa_, p. 178.

Fructification plasmodiocarpous, with a tendency to form distinct sessile, globose sporangia, color brownish red; capillitium a sparingly branched network, with free ends few, the thread marked by seven or eight faint spirals, the interspaces narrow, dull red in color, and 2.5 mu in diameter; spores yellow, delicately warted, 10-10.5 mu.

This is doubtless a very rare species. In the description we have followed Dr. Rex, _l. c._, as being more to the point for American forms. It is not improbable that the American material may after all be distinct, as discrepancies, if one may judge by descriptions, are not few. Lister, who had a slide from Dr. Rex, considers the European and American forms the same.

In outward appearing, plasmodiocarpous phases of this species very closely resemble forms of _Licea_ or _Ophiotheca_, and are in consequence often wrongly labeled.

Toronto; Montana--_Anderson_. To be looked for north and west.

3. HEMITRICHIA OVATA (_Pers._) _Macbr._

1796. _Trichia ovata_ Pers., _Obs. Myc._, I., p. 61, and II., p. 35.
1863. _Trichia abietina_ Wigand, _Pringsh. Jahr._, III., p. 33,
Tab. ii., Fig. 11.
1875. _Hemiarcyria wigandii_ Rost., _Mon._, p. 167.

Sporangia crowded or sometimes closely gregarious, sub-globose or turbinate, shining yellow, sessile, the peridium thin, iridescent; capillitium a tangle of sparingly branched yellow or ochraceous-yellow threads, rather slender, 3-5 mu, marked by one or two prominent spiral bands forming a loose somewhat irregular spiral, the free ends not infrequent, inflated and rounded; spore-mass yellow or yellow-ochraceous, spores by transmitted light pale yellow, distinctly and sharply spinulose, but not netted, 10-11 mu.

A rare and beautiful species, distinguished well by the small size, about .5 mm., by the thin iridescent peridium, as by the microscopic characters of the capillitial threads.

There is no doubt that this is Persoon's _Trichia ovata_. His description is accurate in all that pertains to external features, and Rostafinski, _App._, p. 41, explicitly says that he _saw_ in Persoon's herbarium specimens of the species bearing the name cited. Just why Rostafinski did not here adopt the older name is not clear, nor is there excuse for abandoning Wigand's name were Persoon's invalid. According to Lister, _Trichia nana_ Mass., from Maine, is the same thing. Persoon, _l. c._, gives a synonymy which, in the nature of case, is unverifiable, the specific characters being microscopic.

Fries, _Syst. Myc._, III., p. 187, confirms Persoon and takes pains to say that the color separates it from _T. chrysosperma_ with which it is sometimes compared.

Rare. Maine, Massachusetts, New York, Ohio, Toronto.

4. HEMITRICHIA VESPARIUM (_Batsch_) _Macbr._

PLATE III., Figs. 2 and 2 _a_.

1786. _Lycoperdon vesparium_ Batsch, _Elench. Fung._, pp. 255, 256,
Fig. 172.
1794. _Trichia rubiformis_ Pers., _Roem. N. Bot. Mag._, I., p. 88.
1875. _Hemiarcyria rubiformis_ (Pers.) _Rost., Mon._, p. 262.

Sporangia clustered or crowded, rarely single, clavate or subcylindric stipitate or sessile, dark wine-red or red-black in color, the peridium in perfect specimens glossy or shining metallic, opaque; stipes solid, usually blent together, concolorous; capillitium of intertwisted slender threads, sparingly branched, marked by three or four spiral ridges, abundantly spinulose, the free tips also acuminate, terminating in a spine, the whole mass dull red. Spore-mass brownish-red, spores by transmitted light reddish-orange, very distinctly warted, sub-globose, 10-12 mu.

A most common species, on rotten wood everywhere, especially in forests. Recognized generally at sight by its color and fasciculate habit. The peridium shows a tendency, often, to circumscissile dehiscence, and persists long after the contents have been dissipated, in this condition suggesting the name applied by Batsch, _vesparium_, wasp-nest. The capillitium is remarkably spinescent, the branching of the threads, rare. Rostafinski describes the spores as smooth; they seem to be uniformly distinctly warted. The plasmodium is deep red, and a plasmodiocarpous fructification occasionally appears.

Throughout the whole range, New England to Washington and Oregon, south to Nicaragua; Toronto.

5. HEMITRICHIA STIPATA (_Schw._) _Macbr._

PLATE I., Figs. 8, 8 _a_, 8 _b_.

1834. _Leangium stipatum_ Schw., _N. A. F._, p. 258, No. 2304.
1876. _Hemiarcyria stipata_ (Schw.) _Rost., Mon. App._, pp. 41, 42.
1894. _Arcyria stipata_ (Schw.) Lister, _Mon. Mycetozoa_, p. 189.

Sporangia distinct, crowded, cylindric or irregular, overlying one another, rich copper-colored, metallic, shining, becoming brown, stipitate; peridium thin, the upper portion early evanescent, the base persistent as a cup, as in _Arcyria_; capillitium concolorous, the thread abundantly branched to form a loose net, with many free and bulbous ends, pale under the lens, marked by three or four somewhat obscure spiral bands and a few wart-like or plate-like thickenings; stipe very short; spore-mass reddish, spores by transmitted light pale, nearly or quite smooth, 6-8 mu.

This species is known at sight by its peculiarly beautiful tint when fresh, as by the crowded prolix habit of the singular overlying sporangia. The netted capillitium and the evanescent peridium suggests _Arcyria_, but there are abundant free tips, and the threads are unmistakably spirally wound, especially in the large, handsome sporangia characteristic of the Mississippi valley. It is a boundary form unquestionably. The stipe is generally very short, about one-tenth the total height; sometimes, when the peridium is more globose, the stipe is proportionally longer. Specimens from Iowa show fructifications several centimetres long and wide.

Not rare. New England to the Black Hills and south.

6. HEMITRICHIA LEIOCARPA (_Cke._) _Macbr._

1877. _Hemiarcyria leiocarpa_ Cke., _Ann. Lyc. Nat. Hist. N. Y._,
XI., p. 405.
1891. _Hemiarcyria varneyi_ Rex, _Proc. Phil. Acad._, p. 396.

Sporangia simple, obovate or pyriform, rarely almost globose, pallid, with a stem of the same color, as long as the diameter of the sporangium; spore-mass and capillitium concolorous, or with slight ochraceous tint; capillitium forming a loose net, the tubes branching in a reticulate manner; spirals three, thin, prominent, along the convex sides of the tubes mixed with a few obtuse spines; spores globose, with a thin membrane, 12-14 mu.

Such is the original description of this distinctly American species. _H. varneyi_ Rex should differ in having spirals seven or eight, and spore only 6.25 mu. Mr. Lister, who has compared types of both species, declares them the same! The present writer has been unable to secure authentic specimens.

Pennsylvania.

7. HEMITRICHIA INTORTA _List._

1891. _Hemiarcyria intorta_ Lister, _Jour. Bot._, p. 268.
1891. _Hemiarcyria longifila_ Rex, _Proc. Phil. Acad._, p. 396.
1894. _Hemitrichia_ intorta List., _Mycetozoa_, p. 176.

Sporangia gregarious, globose-turbinate or pyriform, golden-yellow, stipitate; peridium thin, translucent, shining, opening at the summit irregularly, leaving a funnel-shaped receptacle below; stipe dark red brown, solid, rugulose; capillitium of threads sparingly branched, but looped and doubled upon themselves and constantly intertwisted, orange-yellow, 3-4 mu in diameter, with spirals four, sparingly spinulose, even and regular, the longitudinal striae conspicuous; spores in mass concolorous, under the lens yellow, delicately warted, globose, 9-10 mu.

Concerning this species, Dr. Rex says: "Externally this species resembles _H. clavata_ Pers., and has probably often been mistaken for it. The capillitium, however, in its structural details and habit of growth, is widely different. The partial untwisting of the loops of the capillitium by drying, after the rupture of the sporangium, causes it to be projected and elongated sometimes two or three times the length of the sporangium." Outwardly the open sporangium, by the projecting free tips, reminds one of a trichia. The capillitium is like that of _H. vesparium_, but less rough, and, of course, different in color.

Rare. Fairmount Park, Philadelphia; Ohio, Iowa.

8. HEMITRICHIA CLAVATA (_Pers._) _Rost._

PLATE III., Figs. 1, 1 _b_.

1794. _Trichia clavata_ Pers., _Roem. N. Bot. Mag._, I., p. 90.
1873. _Hemitrichia clavata_ Pers., Rost., _Versuch_, p. 14.
1875. _Hemiarcyria clavata_ (Pers.) Rost., _Mon._, p. 264.
1893. _Hemiarcyria ablata_ Morg., _Jour. Cin. Soc._, p. 30.
1893. _Hemiarcyria funalis_ Morg., _Jour. Cin. Soc._, p. 32.

Sporangia clavate or turbinate, gregarious, scattered or crowded, yellow, olivaceous or brownish, stipitate; the peridium generally thin, evanescent above, breaking away so as to leave a more or less definite cup beneath; stipe about one-half the total height, reddish, reddish-brown, or blackish, hollow about half-way down; capillitium various, yellow or ochraceous, made up of slender threads more or less freely branched and netted, bearing four or five regular, even, spiral plates which project sharply and are generally smooth, the free extremities numerous or almost none, swollen, or simply obtuse; spore-mass concolorous, spores by transmitted light pale yellow, globose, minutely but distinctly warted, 8-9 mu.

This cosmopolitan species is generally one of the first brought in by the collector, its color and comparatively large size, 2-3 mm. high, making it conspicuous. Nevertheless, we are not able to recognize it in the descriptions of the older authors. Rostafinski quotes Schmiedel, _Icones_, 1776, as affording the earliest account of the species, but neither his description nor figure is definitive. Even Bulliard fails us here, and is differently interpreted by different authors. Persoon's description is none too good, but is reenforced by Fries and Rostafinski. The capillitium is variable both in the degree of smoothness presented, and the number of free ends, and the amount of branching. The spores in all specimens we have examined are remarkably constant in size and surface. In typical specimens free ends are easily discoverable, the branching forms a definite net, and the perfectly formed capillitial thread is smooth. In some American forms--developed under less favorable circumstances?--the net is less determined, the free ends are many, and the spirals minutely rough. Here may be placed _H. funalis_ Morgan, _l. c._

Widely distributed. New England to Colorado, south to Mexico.

9. HEMITRICHIA STIPITATA (_Mass._) _Macbr._

1889. _Hemiarcyria stipitata_ Mass., _Jour. Mic. Soc._, p. 354.
1893. _Hemiarcyria plumosa_, Morg., _Jour. Cin. Soc._, p. 29.

Sporangia scattered, seldom crowded, obovoid or turbinate, olivaceous yellow, stipitate; the peridium smooth without, granulose within, evanescent above, persisting as a funnel-shaped cup below; the stipe long, reddish or blackish, rising from a small hypothallus; capillitium of threads 5-6 mu thick, very much branched, forming a dense net, free ends none, or not evident; the sculpture as in _H. clavata_, smooth and regular; spore-mass yellow; spores by transmitted light yellow, minutely warted, 7-8 mu.

This form corresponds in nearly every respect with _H. clavata_, except in the structure of the capillitium. The color is rather ochraceous, dirty yellow, and the stipe is proportionally longer and darker, but the form of the net is positive and gives to the species a decidedly striking and unique appearance, so that it may be recognized by the naked eye. It looks like an arcyria and for this reason Professor Morgan said _H. plumosa_. Lister regards it as the same as our number 8.

Common. Ohio, Illinois, Missouri, Iowa, and west; south to Mexico.

10. HEMITRICHIA MONTANA _Morgan._

Sporangia scattered or gregarious more or less closely, globose, whitish, sessile or very short stipitate; the peridium opaque, dull white, persistent below; capillitium deep yellow, the threads abundantly branched, forming a compact network, 7 mu wide, bearing spirals five or six, uneven and irregular, or anon interrupted, conspicuously spinulose or warted, free tips not lacking, generally inflated; spore-mass yellow, spores by transmitted light pale, nearly colorless, distinctly warted, 10 mu.

Recognizable by its peculiar pallid, sessile sporangia, as by the internal structure. Perhaps related to _Hemiarcyria bucknalli_ Mass. Our specimens are from Mr. Morgan, of Ohio, with the statement that they were collected in the San Bernardino Mountains, California, by Mr. S. B. Parrish; collected later from Monterey south.

Common throughout south-western states to lower California.

=2. Calonema= _Morgan._

1893. _Calonema_ Morgan, _Jour. Cin. Soc._, p. 33.

Sporangia sub-globose, crowded or superimposed, irregular sessile; hypothallus none; capillitium of slender tubules, arising from the sporangium base, branched, marked with branching veins in an irregular reticulation, and terminating in free extremities. Spores yellow.

1. CALONEMA AUREUM _Morgan._

PLATE XIII., Figs. 2, 2 _a_, 2 _b_, 2 _c_.

1893. _Calonema aureum_ Morgan, _l. c._

Sporangia crowded or heaped in scattered clusters; peridium thin, golden yellow, adorned with intricate radiating veinlets capillitium of threads more or less branched, attached below, free above, the surface to the very tips venulose, interrupted with rings or fragmentary spirals, the apices bulbous and obtusely conical; spore-mass yellow, spores by transmitted light bright yellow, covered by a network of interlocking plates, as in _T. favoginea_, globose, 14-16 mu.

A curious form, related to _Hemitrichia_, much as _Oligonema_ is to _Trichia_. Related to both the genera first named, but distinct, in the peculiar sculpture, from _Hemitrichia_, and from _Oligonema_ in that the threads are not entirely free. Professor Morgan's original determination, founded on Ohio materials is confirmed by material sent us by Professor Underwood from Alabama.

=3. Trichia= (_Haller_) _Rost._

1768. _Trichia_ Haller, _Hist. Stirp. Helv._, III., p. 114, in part.
1875. _Trichia_ (Haller) Rost., _Mon._, p. 243.

Sporangia distinct, sessile or stipitate; capillitium of distinct elastic threads, free acuminate at each end, yellow or more rarely reddish or brown; spores generally yellow.