The North American Slime-Moulds Part 52

Lister was right. _R. lobata_ List. (now _Liceopsis lobata_ List.) Torr., occurs in various parts of Europe, while our American species of _Enteridium_ is yet to be discovered on that side of the sea!

Were the latter native to the old world at all, it had surely been seen long ago. It is large and fine, and could not have escaped the famous collectors of the last two hundred years. Although it has been sent by students from this side of the ocean to Europe for more than thirty years, it has not even advent.i.tiously appeared.

It therefore appears that our American species is known to Europe through Mr. Wingate's reference only.

Twenty years ago in correspondence with Mr. Wingate it was learned that the material received by him from M. Roze was but a small fragment, crushed flat, and even this was at that time no longer in evidence. This specimen was itself _not part of the gathering submitted to Rostafinski_; but only the fragment of something _appearing in 1890 in the same locality_!

... "something not the same, But only like its forecast in men's dreams."

When we further reflect that the spores of species of several of the forms now in review, _Tubifera_, _Reticularia_, _Enteridium_, are not without difficulty distinguished, it is easy to see that Mr. Wingate's specific reference has narrow foundations to say the least. It seems now likely that Father Torrend's _Liceopsis_, _Reticulara lobata_ R., M.

Roze's aftermath, and all, are but the depauperate forms of some tubifera!

_E. rozeanum Wing._, is therefore the synonym for an ill-defined something in Western Europe and need not further here concern us as far material reference goes.

In any case, what induced Mr. Wingate to pull Rostafinski's uncertain description of a problematic form across the sea, to attach it to our clearly defined and well known American species, changing the Polish description the while to make it fit, is hard to understand; especially in view of the fact, by Wingate admitted, that Rex had in his letters to Morgan already named the American type _Enteridium umbrinum_. The two students differed as to generic reference, and later on Morgan published _Reticularia splendens_ Morg.; rather than _R. umbrina_ (Rex) Morg.

because he was using _R. umbrina_ Fr. for what is generally known as _R.

lycoperdon_ (_Bull._)

It would then appear that when Wingate sought to impose the Rostafinskian specific name upon our American form by changing (fixing!) Rostafinski's generic reference, and by re-writing the specific description from the pages of the _Monograph_ in order to claim ident.i.ty, he was entirely without justification, especially since he knew the species appropriately named by his colleague, Dr. Rex, and had the name as used in the Rex and Morgan correspondence.

In brief; Mr. Wingate proceeded to re-describe Rostafinski's rozean specimen and referred a long-known American form (very different) to the European specimen as type. Wingate's description is right; he had the American material before him; but his cited type is worthless, an entirely different thing.

Does the reader care to see what the European _type_ of our common form, Wingate _teste_, really looks like, let him consult the _Jour. of Botany_, Vol. XXIX., p. 263, 1891.

2. ENTERIDIUM OLIVACEUM _Ehr._

1818. _Enteridium olivaceum_ Ehr.

aethalium depressed flat, oval or elongate, .3 cm. in extent, .6 mm.

thick when fresh, glossy, smooth, greenish-olivaceous-brown; within a spongy net-work representing sporangial walls which are thin, pale olivaceous, perforate by circular openings, meshes surrounded by wide plates; spores in cl.u.s.ters, six or more together, ovoid, distinctly warted at the wider end, pale olivaceous, 9-11 .

This, the type of the genus, is a very distinct species of this by its structure readily distinguished form. Fries thought the species might represent a less perfectly-developed reticularia, and therefore wrote _Reticularia olivacea_ noting, however, the cl.u.s.tered spores and the lack of hypothallus.

Common, as would appear, in Europe and in S. America; rare with us.

Reported from N. Hamps.h.i.+re and we have one specimen from Colorado.

3. ENTERIDIUM MINUTUM _Sturg._

1917. _Enteridium minutum_ Sturg., _Mycologia_, IX, p. 328.

aethalia rounded or elongate, pulvinate, pale umber in color, seated on a broad membranous base, 1.5-2 mm. in diameter; wall wrinkled and usually marked with small scattered pits, pale-yellow, membranous; walls of component sporangia, membranous, minutely roughened, perforated with round openings, the margins of which show many free threads; or reduced to irregular, anastomosing strands arising from the base of the aethalium, with membranous or net-like expansions at the angles and with many delicate, free, pointed ends. Spores pale-yellow, usually united in twos or threes, and ovoid or flattened on one side; when free, globose, very minutely spinulose, 9.5-10.5.

Colorado: _Dr. Sturgis._

=3. Dictydiaethalium= _Rostafinski_

1873. _Dictydiaethalium_ Rost., _Versuch_, p. 5.

1875. _Clathroptychium_ Rost., _Mon._, p. 224.

aethalium depressed, flat; the sporangia erect, regular, prismatic by mutual pressure, the peridia convex above, wanting at the sides and within the aethalium represented by vertical threads marking the angles and pa.s.sing from base to summit.

This genus is readily recognized by the internal structure of the aethalium. The lateral wall-openings, which, as we have seen, characterize the sporangia of the preceding genus, here become extreme, occupying to such extent the lateral wall-s.p.a.ce of each sporangium that only threads remain to mark the vertical angles.

In 1873 Rostafinski applied the generic name here adopted, because he thought he discovered close relations.h.i.+ps with _Dictydium_. In 1875, believing his first impressions erroneous, and desirous that the nomenclature might not at once mislead the student and perpetuate the memory of his own mistake, the same author proposed the name by which the genus has generally ever since been known--_Clathroptychium_.

However sensible the latter conclusion reached by our Polish author, it is plainly contrary to all rules of priority.

Our region shows but a single widely distributed species,--

1. DICTYDIAETHALIUM PLUMBEUM (_Schum._) _Rost._

PLATE I., Figs. 2, 2 _a_, 2 _b_.

1803. _Fuligo plumbea_ Schum., _Enum. Saell._, No. 1410.

1833. _Licea rugulosa_ Wall., _Cr. Fl. Ger._, IV., p. 345.

1873. _Dictydiaethalium plumbeum_ (Schum.) Rost., _Versuch_, p. 5.

1875. _Clathroptychium rugulosum_ (Wallr.) Rost., _Mon._, p. 225.

1894. _Dictydiaethalium plumbeum_ Rost., List., _Mycetozoa_, p. 157.

aethalium thin, very flat, olivaceous or ochraceous, smooth, under the lens punctate, in section showing the columnar or prismatic sporangia, which are normally six-sided, having at the edges six simple threads, the remains of peridium, extending from base to apex, where the peridium remains intact, arcuate; hypothallus prominent, radiating far around the aethalium, silvery white; spores in ma.s.s, ochraceous, or dull brownish yellow, by transmitted light almost colorless, rough 9-10 .

Not rare, on decaying logs, especially of _Tilla americana_, where in the same place successive fructifications follow each other sometimes for weeks together in the latter part of summer and early fall. The aethalium is generally elliptical or elongate, 2-3 cm. in extent, sometimes irregular or branched, varying in color according to degree of maturity, weathering, etc. Plasmodium at first watery, then pink, or flesh-colored.

Eastern United States; common. Toronto;--_Miss Currie._

_E._ CRIBRARIACEae

Sporangia distinct, more or less closely gregarious, stipitate, the peridium opening, especially above, by a well-defined network formed from thickenings in the original sporangial wall.

=Key to the Genera of the Cribrariaceae=

_A._ Peridial thickenings in form of an apical net with definite thickenings at the intersections of the component threads 1. CRIBRARIA

_B._ Peridial thickenings in form of parallel meridional ribs connected by delicate transverse threads 2. DICTYDIUM

=Cribraria= (_Pers_) _Schrader._

1794. _Cribraria_ Persoon, Romer, _N. Bot. Mag._, I., p. 91, in part.

1797. _Cribraria_ Schrader, _Nov. Gen. Plant._, p. 1, in part.

1875. _Cribraria_ Rostafinski, _Mon._, p. 229.

Sporangia distinct, gregarious or closely crowded, globose or obovoid, stipitate; the stipe of very varying length; the peridium simple, marked within by distinct and peculiar, granular, thickenings, which below take the form of radiating ribs, supporting the persisting cup, _calyculus_, and above, by extremely delicate anastomosing branches, unite to weave a more or less regular net with open polygonal meshes; spores various, more often yellowish or ochraceous, sometimes brown, reddish, or purple.

The genus _Cribraria_, as limited by Persoon, included all forms in which the peridium is thin, evanescent half-way down, or entirely, and in which capillitium, as Persoon regarded the case, is formed of a network of reticulate threads surrounding the spores. Schrader redefined the genus; opposed Persoon's view as to the capillitial nature of the net, and separated the genus _Dictydium_, but by imperfect limitations,--in fact, chiefly because of the more completely evanescent peridium. Fries follows Schrader. Rostafinski first clearly separated the two genera, and his cla.s.sification is here adopted. Nevertheless, after reviewing the subject entire one is more and more inclined to appreciate the commendation of Fries; "Auctor Schrader, qui insuper plurimas species detexit, et hoc et sequens genus ita proposuit ut sequentes vix aliquid addere valuerint."