The North American Slime-Moulds Part 36

3. LEPIDODERMA CHAILLETII _Rost._

PLATE XVIII., Figs. 6, 6 _a_, 6 _b_.

Sporangia distinct, coalescent or plasmodiocarpous, large, when isolated 1-1.5 mm., dull drab in color, very spa.r.s.ely sprinkled with white tetrahedral or irregular scales; the peridium thin, more or less translucent, rugulose, dull brown, persistent; columella none; capillitium abundant, under the lens purple-brown, sparingly branched, even, stout, rigid, no calcareous deposits nor vesicles; spores 8-10 , minutely warted, fuliginous.

Yosemite Canon, California, _Prof. B. s.h.i.+mek._

This is, no doubt, similar to _L. carestianum_ but differs in the size and habit of the sporangia, and in the fact that the capillitium is uniform throughout, whatever the style of fructification, and in the size, color, and surface characters of the spore.

Evidently not _Didymium granuliferum_ Phill. Both will, no doubt, be again collected, and we shall then have much needed light.

Nor is this quite Rostafinski's species as cited. The spores are much smaller; Rostafinski says 10-12 or more, and calls for a distinctly netted capillitium, the surface strongly marked by abundant calcareous crystals. Ours may be a different thing.

=5. Colloderma= _G. Lister_

1910. _Colloderma, Jour. of Botany_, XLVIII., p. 312.

Peridium double; the outer gelatinous, the inner membranaceous; capillitium intricate, limeless.

COLLODERMA OCULATUM (_Lipp._) _G. Lister._

1894. _Didymium oculatum_ Lipp., _Verh. Zo-Bot. Ges. Wien_, XLIV., p. 74.

1910. _Colloderma oculatum_ (Lipp.) G. List., _Jour. Bot._, XLVIII., p. 312.

Sporangia gregarious, globose, or sub-globose, sessile or short-stipitate, olivaceous or purplish-brown, smooth and s.h.i.+ning, the outer peridium gelatinous, thickened by moisture, hyaline; stipe dark brown; columella none; capillitium as in _Didymium_ purplish-brown, colorless at the tips; spores spinulose, fuscous, about 12 .

New Hamps.h.i.+re, Europe.

Our specimens from the late Dr. W. G. Farlow who collected it in New Hamps.h.i.+re. Swollen by immersion in water the sporangia take on an eye-like appearance, oculate, etc.

=EXTRA-LIMITAL=

PHYSARINA _von Hohnel._

1909. _Physarina_ von Hohnel, _Akad. Wiss. Wien; Math-nat. KL._, CXVIII., p. 431.

Sporangium wall rough with blunt spine-like processes, otherwise as _Diderma_.

One species, _op. cit._, p. 432, _P. echinocephala_ v. Hohn.

Java. Might as well be called _Diderma echinocephalum_, one would think.

Structure is that of _Leangium_. The striking character is a surface modification of the outer peridium, according to the description.

ORDER II

=STEMONITALES=

Capillitium present, thread-like, arising in typical cases from a well-developed columella; spores in ma.s.s, black or violet-brown, more rarely ferruginous.

=Key to the Families of Stemonitales=

_A._ Fructification aethalioid, capillitium poorly defined; columella rudimentary or none AMAUROCHaeTACEae

_B._ Fructification of distinct sporangia, capillitium well defined; the columella generally prominent, long and abundantly branched throughout STEMONITACEae

_C._ Sporangia distinct; capillitium developed chiefly or only, from the summit of the columella LAMPRODERMACEae

_A._ AMAUROCHaeTACEae

Fructification aethalioid, an inch or two in diameter, in form varying with the habitat and place; capillitium dendroid, consisting of rather stout branches which rise irregularly more or less vertically from the hypothallus, branch repeatedly, often anastomose to form a network, especially toward the periphery; spores black.

A single genus--

=1. Amaurochaete= _Rostafinski_

1873. _Amaurochaete_ Rost., _Versuch._, p. 8.

The genus _Amaurochaete_ as defined by Rostafinski and the genus _Reticularia_ as represented by _R. lycoperdon_ Bull. stand, the expression, perhaps, of not dissimilar histories. Whether in regressive or progressive series, each to-day presents a case of arrested development. Each in aethalioid fructification, reveals a ma.s.s of involved individual (?) sporangia, so imperfectly developed that their outlines can be inferred rather than anywhere, with absolute definiteness, certainly ascertained. Perhaps, because similar sporangia in the group to which either belongs, do come under other circ.u.mstances, to more perfect individual form and function--perhaps for this reason we may look upon these aethalia as exhibiting a suspended performance; the sporangia have failed to go forward to what was evidently a possible, though apparently not an essential destiny in form and figure. For the care and dispersal of the spores, achievement must surely be somewhat impaired. Whatever the measure of such inefficiency, among the _Stemonitales Amaurochaete_ shows the acme, as _Reticularia_ among the brown-spored forms.

In _Amaurochaete_ the individuality of anything like separate sporangia is less clear. The view afforded, however, by a good vertical section of a well-developed colony or cus.h.i.+on is interestingly arborescent. Ragged, dendroid stems arise, dissipated above into a network most intricate, a "pleached arbor" if you please. The resemblance of the overhead net to that presented by a stemonitis or comatricha is very striking.

=Key to the Species of Amaurochaete=

_A._ Capillitium rigid, irregular spores rough 1. _A. fuliginosa_ _B._ Capillitium soft, woolly, cincinnate, spores as in _A_ 2. _A. tubulina_

1. AMAUROCHaeTE FULIGINOSA (_Sowerby_) _Macbr._

PLATE V., Figs. 8, 8 _a_.

1803. _Lycoperdon fuliginosum_ Sow., _Eng. Fung._, t. 257.

1805. _Lycogala atrum_, Alb. & Schw., _Consp. Fung._, p. 83.

1875. _Amaurochaete atra_ (Alb. & Schw.) Rost., _Mon._, p. 211.

Fructification aethalioid, varying in form and size, if on the upper side of the substratum, pulvinate, if below pendent and almost stipitate, covered with a delicate cortex, at first s.h.i.+ning, soon dull, black, fragile, and early dissipated; hypothallus long-persisting, supporting the capillitium, which is extremely variable, irregular, and for its perfection dependent upon the form a.s.sumed by the aethalium, and the conditions of weather, etc., under which it matures, sometimes, especially when prostrate, in a very much depressed aethalium, spreading into long fibrous threads, again under better conditions rising in columella-like forms, supporting a peripheral net; spores dark brown or black, irregularly globose, spinulose, 12.5-15 .

Common in Europe, and probably not uncommon in this country wherever pine forests occur. Specimens before us are from New England and New York, Ohio, Carolina, Colorado. Canada.

Sowerby, in his comment on plate 257, _Eng. Fungi_, says: "It appears to consist of branching threads affixed to the deal and holding a dense ma.s.s of sooty powder. Over the whole is a thin, deciduous pellicle."

This description seems to be applicable to nothing else. The figure amounts to little. Fries recognizes the English description, as does Rostafinski, but both authors adopt the later name given by Albertini and Schweinitz, simply because of the excellent detailed description found in the _Conspectus_.