The North American Slime-Moulds Part 69

[17] See Jahn, _Myxomyceten Studien_ No. 8, Berlin 1911.

[18] In discussing these species the reader may be referred to Professor Harper's study of cytology, _Bot. Gazette_, vol. x.x.x., p. 217. It is probable that in all these aethalioid forms the effect of disturbance, transfer to laboratory, is likely to be quite p.r.o.nounced. Giant spores are often seen, doubtless due to arrested cleavage in the procedure described by Dr. Harper: a giant spore is penultimate or antepenultimate in series; should, on this theory, occasionally, at least, show more than one nucleus.

[19] Prior to Persoon the physarums were variously referred: _Lycoperdon_, _Sphaerocarpus_, _Trichia_, etc. It seems unnecessary to quote the synonymy further here.

[20] Persoon's first-named species is _P. aureum_; see _Romer Neu. Mag.

f. d. Bot._, I., p. 88. 1794.

[21] Fries (_Sum. Veg. Scand._, p. 454) described the new genus in the following words: Tilmadoche. Fr. Physari spec. S. M. Peridium simplex, tenerrimum (_Angioridii_) irregulariter rumpens. Capillitium intertexto-compactum, a peridio solutum liberum, sporisque inspersis fuscis. Columella o.

1. T. leucophaea. Fr.

2. T. soluta. (Schum.)

3. T. cernua. (Schum.)

[22] See also _Inaug. Diss._, H. Ronn, _Schr. d. Naturw. Ver. f. Schl.

Holst._, XV., Hpt. I., p. 55, 1911.

[23] Inasmuch as there has been decided difference of opinion in reference to this particular species,--all judges readers of the same original description,--it has seemed wise to submit an English translation from the celebrated _Monograph loc. cit._

"24. Physarum diderma _Rfski._

"Sporangia sessile, globose, adnate by a narrow base, white. Peridium double; the outer thick, strongly calcareous, very distinctly set off from the thin inner one by an air-filled s.p.a.ce; the calcareous nodules many, angular, loosely developed within to form a pseudo-columella; spores dark violet, spinescent, 9.2-10 in diameter.

"_Opis._ This physarum looks extremely like a diderma.

"The sporangia stand either aggregated or bunched together in heaps of five to twelve, adnate to the hypothallus by a narrow base, etc."

Ma.s.see, _Mon._, p. 304, translated this description, but misunderstood what is said of the columella and is inclined to think the author did not know a diderma when he saw one; which is pretentious, to say the least!

[24] See also, after all our trouble, _Jour. Bot._, LVII., p. 106.

[25] See Fries, _Syst. Myc._, Vol. III., pp. 130, 137, Rost., _Mon._, p.

127, and _Rep. N. Y. State Mus._, x.x.xI., p. 55.

[26] It would seem that M. Ma.s.see would have written _T. reniformis_, were this authentic.

[27] For further synonymy, see under _P. auriscalpium_, No. 49.

[28] Robt. E. Fries, _Ofvers. K. Vetens. Akad. Forh._, 1899, No. 3, p.

225.

[29] The Polish author wrote Tilmadoche instead of Physarum in each case cited.

[30] Forms cited are chiefly those likely to be found in our neighboring tropics, West Indies, etc.

[31] These little structures have a fairly architectural appearance and may be called trabecules,--trabeculae, little beams.

[32] Dr. Cooke, who used the microscope, applied the _Monograph_ description to British forms occurring on leaves; proceeded further and found the same situation in New York. Mr. Ma.s.see gives the species wide range with spores 8-10 ; average 9 ; only a fraction too large; evidently none 12-15 .

[33] If a sporangium of _L. tigrinum_ be mounted in water and treated to weak solution of hydro-chloric acid we may easily discover that the crystals, which so wonderfully adorn the outer wall in this and other species, consist, in part at least, of calcium carbonate. We may also discover that in the case before us the crystal or scale lies indeed enclosed in a filmy sac of organic origin, and that could we have seen the outer peridium as it came to form, we might probably have found it made up largely of an ectosarcous foam in whose cavities the excreted calcium found place for tabulate crystallization. In other species listed, conditions are different, and the crystals a.s.sume a different shape. The phrase "bicarbonate of lime" quoted in this connection in the former edition of this work from Mr. Ma.s.see's _Monograph_, etc., is not clear.

[34] Doubtless immature; _v. Mitteil. Naturwiss. Gesell. Wintert._, VI., p. 64, Lister quoted by Schinz.

[35] Vid. _Mycologia_, N. Y., Vol. IX., p. 328.

[36] See _Addenda, d_, p. 282 following.

[37] In the _Mycetozoa_, 2nd ed., p. 158, is cited _Stemonitis virginiensis_ Rex as a synonym of this variety. By reference to p. 163 of the present volume the Virginian stemonitis is left as Rex a.s.signed it, and if the present variety be synonymous, it should be quoted there.

The treatment of the species _C. nigra_ in the second edition does not establish such fact, nor with three varieties make for any increasing clearness.

[38] It had seemed less necessary to retain the cla.s.sic orthography in this instance since De Bary and Rostafinski both use _Diachea_. But modern scholars.h.i.+p is nothing if not meticulous; it is the fas.h.i.+on in Latin still to keep the digraph, even to the vexation of all men. In the same way when Bulliard wrote _leucopodia_, 'white stockings', he doubtless meant to be exact.

[39] For this citation we are indebted to _Mr. Hugo Bilgram_.

ADDENDA

a. This volume is as we see, a descriptive list of the various forms of the Myxomycetes in so far as these have come to the personal notice of the writer.

Each form is designated, as is usual in discussing objects of the sort, by a particular binomial name, followed, in abbreviated form, by the name of the student or author who in describing the form in question used the combination. Thus _Stemonitis splendens_ was first described by Rostafinski, and the name he thus used is applicable to the form he described, wherever found, and to _nothing else_.

The proper naming of any specimen would thus appear to be a very simple matter. Such, however, is often not the case, particularly where we are concerned with species long familiar to science. Such often have received, at different times, and at the hands of the same author, or certainly of different authors, different names, given for various reasons; so that one who would refer to, or discuss, a single specimen to-day finds himself often in great uncertainty, confronted by a mult.i.tude of binomial combinations all thought to refer to the same particular thing.

By general consent, of course, we strive to ascertain the oldest name on the list; the first that is really and clearly applicable, and we write all other names down as synonyms. In this volume a list of synonyms often accompanies the description; precedes it, showing, year by year, the history of the case; an abstract in fact of the t.i.tle, as at last approved. The preparation of such an abstract is very troublesome, but is believed to be worth the trouble; must be made, indeed, if we are ever in our discussions to be sure that when we speak or write in America, we are dealing with the same thing intended by the man who speaks or writes in England, or elsewhere.

The s.p.a.ce occupied in synonymy, is therefore by no means wasted. By and by, if we succeed in establis.h.i.+ng a nomenclature on which competent judges can agree, a thing not at all improbable, almost now attained, the lists may gradually disappear as having historical value only.

b. Taxonomy, in any field, is of necessity concerned with history. For his own sake, no student can ignore the thought and work of his predecessors. No man ever sees nature in completeness, nor even the small part of the world to which he devotes attention. He needs every possible a.s.sistance, especially the observations of intelligent men. The present author rejoices to acknowledge the a.s.sistance found in volumes written in Europe during the last two hundred years. Such men as Persoon, Bulliard, Schumacher, Schrader, Fries, are deservedly famous; they laid the foundations of mycologic taxonomy. No student can afford to miss _Elias Fries_; his genius, spirit and scholars.h.i.+p ent.i.tle him to the recognition and sympathy of every lover of the intellectual life.

c. The considerations just mentioned may, indeed do, sometimes act as a handicap to the American student, for the simple reason that he comes later to the field of time. He must naturally defer to the decision of men in Europe who are supposedly familiar with original types. An American specimen is presumably the same as one occurring elsewhere in similar lat.i.tude and environment. It becomes evident after while that only in certain instances is this undoubtedly the fact. The flora of the American continent has been sufficiently disjoined in s.p.a.ce and time from Europe to permit extensive differentiation even in these minor forms, so that we have indeed in the groups we study many species, some genera, definitely autochthonous, more it is believed than are now suspected. An attempt to bring a specimen under the terms of a species described in Western Europe is not seldom an error. It becomes evident, as we go forward, that in eastern North America there are forms not only not described in European literature, but really not, part of European flora, not even advent.i.tiously.

d. Many of the more minute species with which this volume has to do are very elusive, very difficult; for one reason,--perhaps in itself sufficient,--because of their minuteness, and consequent apparent paucity. They may be common, but none the less seldom seen. The comatrichas afford an ill.u.s.tration. There are several very small species. _C. pulch.e.l.la_, _C. laxa_, _C. ellisii_ may be mentioned. _C.

pulch.e.l.la_ has been studied nearly a hundred years and has a synonymy accordingly. In 1875 Rostafinski in the material, and among the descriptions, thought he recognized two distinct forms, and went on to give them names; the first in honor of Persoon, _C. persoonii_, should show an ovate or ovate-cylindric outline with ac.u.minate tip; the second should be truncate and represent a type first described by Berkeley under a name given by Babington, _C. pulch.e.l.la_. Berkeley's drawing shows a sporangium with tip ac.u.minate! Lilac or violaceous tints attracted attention in the spores of _C. persoonii_ only; in _C.

pulch.e.l.la_ all is ferruginous. Curtis is especially commended for noticing the fact in describing _S. tenerrima_, here included as we see.

_Comatricha gracilis_ Wing. is slender, cylindric and has small spores hardly reaching 6 ; should perhaps be now set out as a separate species; it is evidently purely an American phase.

Our figures, Plate XII., 16 and 16 _a_, 18 and 18 _a_, show _C.

pulch.e.l.la_ and _C. gracilis_, respectively, extremes. Plate XIII., 4, shows an ovate form not very unusual. This and _C. gracilis_ occur on living leaves.

_C. ellisii_ is another of this minor series, very constant in its delicate beauty, but approaches _C. nigra_ rather than the others here discussed.

_C. laxa_, as the name implies, shows an open construction, suggested, perhaps, by Rostafinski's photographic print, but better brought out by Celakowsky, _Myx. Bohm._, Tab. 2, Figs. 7 and 8.