The North American Slime-Moulds Part 54

_C. minima_ Berk. & C., and _C. microscopica_ Berk. & C. are doubtless the same thing. _Grev._, II., p. 67, 1823. See also _Bot. Gaz._, XIX., 397.

Rare. Pennsylvania, South Carolina, Missouri, Iowa; Black Hills, South Dakota.

4. CRIBRARIA RUFA (_Roth_) _Rost._

PLATE XIX., Fig. 8.

1788. _Stemonitis rufa_ Roth, _Fl. Germ._, I., p. 548.

1794. _Cribraria rufescens_ Pers., Roemer, _N. Mag. Bot._, I., p. 91.

1797. _Cribraria fulva_ Schrad., _Nov. Gen. Pl._, p. 5.

Sporangia scattered, sub-globose or turbinate, dark or reddish orange, .5-.7 mm. in diameter, erect, stipitate; stipe about equalling the height of the sporangium or longer, dark brown or black; calyculus one-third to one-half the sporangium, the margin toothed, the wall ribbed and continuous with the open wide-meshed net; the network deep yellow or orange, the threads flattened; the nodes not thickened, little differentiated; spores concolorous, by transmitted light, pale yellow, verruculose, 5-7 .

Similar to the preceding, but generally much larger and not so much inclined to brown. The size, however, is extremely variable in sporangia from the same plasmodium (reported white), some no larger than those of the species reckoned most minute.

Oregon. _Professor Morton Peck._

5. CRIBRARIA SPLENDENS (_Schrader_) _Rost._

PLATE XIX., Fig. 10.

1797. _Dictydium splendens_ Schrad., _Nov. Gen._, p. 14.

1801. _Cribraria splendens_ (Schrad.) Pers., _Syn. Fung._, p. 191.

Sporangia gregarious, globose, dusky yellow when filled with spores, dull or dusky brown when these are discharged, stipitate; stipe long, 3-4 times the sporangium, subulate, erect-nodding, brown; hypothallus none; network brown, with large meshes, imperfectly defined nodes and flattened threads; calyculus none, its place supplied by nine or ten distinct, firm ribs which radiate from the stipe and support the net, branching to blend with its reticulations; spore-ma.s.s yellow, spores by transmitted light, colorless, smooth or nearly so, 6-7.5 .

Of this species two specimens only are before us, one from Muscatine County, Iowa, and one from Was.h.i.+ngton (state). The species seems thus to have wide range, but to be exceedingly rare. It differs from all other American forms, so far described, in the peculiar development of the calyculus. Rostafinski emphasizes the persistence of the peridial wall and the peculiar gleaming of the metallic tints, displayed by all the structures. These particulars we have not been able to verify. Such characters may be incident to age or conditions of development. At all events, in forms which in all other respects seem to agree exactly with Rostafinski's descriptions, the colors are dull and without any noticeable iridescence. The spores in our specimens are also a little larger than quoted. Rostafinski gives 5-6 ; Ma.s.see, 5-7 .

6. CRIBRARIA AURANTIACA _Schrader._

PLATE XVII., Fig. 3, and XIX., Fig. 7.

1797. _Cribraria aurantiaca_ Schrad., _Nov. Gen. Pl._, p. 5.

Sporangia gregarious, spherical, dusky or yellowish stipitate, nodding; the calyculus variable, generally prominent, more or less distinctly marked by fine, delicate radiating venules, the margin denticulate, the teeth numerous and slender, supporting the well-defined globose net; network made up of very tenuous threads, forming rather small irregular brownish nodules and showing only here and there a free extremity; stipe generally short, two or three times the diameter of the sporangium, sometimes longer, tapering upward, brown, slender, arcuate above; spore-ma.s.s yellow or ochraceous, spores by transmitted light, colorless, 5-6 , almost smooth.

This widely distributed and very variable species is generally recognized by the large sporangia, .5-.9 mm., comparatively short stipe, simple net, and more or less orange color. The color is an uncertain thing even in the sporangia, which rise from one plasmodium. Schrader, however, made this feature so far diagnostic that he placed the more p.r.o.nouncedly yellow forms in the species _C. aurantiaca_ and set off as _C. vulgaris_ forms in which more dusky tints prevail. The dark-colored forms have also usually longer stipes, but so much is dependent upon the climatic conditions prevalent at the time of fruiting, that this feature also is indeterminate. Rostafinski's figures, 21 and 26, Tab. II., show the characteristic nodules and the typical net structure. It is to be observed that Fig. 21 represents higher magnification; otherwise the two figures are very much alike.

New England, New York, Pennsylvania, Maryland and South, Ohio, Was.h.i.+ngton, California; Canada, Toronto.

7. CRIBRARIA DICTYDIOIDES _Cke. & Balf._

PLATE I., Figs. 5, 5 _a_, 5 _b_, and XIX., 6, 6 _a_, 6 _b_.

1881. _Cribraria dictydioides_ Cke. & Balf., _Rav. Fung. Am._, 475.

Sporangia gregarious, of medium size, globose, cernuous, stipitate; the stipe long, slender, tapering upwards, dull brown in color; hypothallus none; the calyculus variable, sometimes well developed, as in _C.

aurantiaca_, sometimes rudimentary or represented only by irregular, node-like ribs; the network delicate, the meshes small, few-sided; the nodules large, prominent, brown, irregular, with several radiating, free, projecting threads, beside the single continuous filaments which pa.s.s from node to node; spore-ma.s.s pale, ochraceous; spores nearly smooth, colorless, 5-7 .

This seems to be the most common _Cribraria_ in the Mississippi valley.

It is generally distinguished by the scant calyculus and the beautiful richness of its clear delicate net. The stellate nodules especially above, emit filamental rays in all directions, but are, notwithstanding, united by single, unpaired threads only. The calyculus is often entirely absent, and this has been supposed the typical condition; but, on the contrary, there often may present itself a cup as distinct as in _C.

aurantiaca_. See, for this variation, _Bot. Gaz._ XIX., p. 398. The rather large sporangia, .6-.7 mm., the nodes joined by single threads, the remaining radiant threads, many or few, but very short--these seem to be the most distinctly diagnostic characters, and these are sufficiently constant to separate this species easily from _C.

intricata_ on the one hand and _C. tenella_ on the other. Mr. Lister considers this merely a form of the next species.

Abundant on rotten logs of every sort, especially oak; common on the lower side of rotting pine planks in wooden walks along the streets everywhere. N. A. F., 2095, seems to belong here.

Pennsylvania, Ohio, North Carolina, Missouri, Illinois, Iowa, Nebraska.

8. CRIBRARIA INTRICATA (_Schrad._) _Rost._

1797. _Cribraria intricata_ Schrad., _Nov. Gen. Pl._, p. 7.

Sporangia gregarious, globose, large, .7-1 mm. in diameter, nut-brown or olivaceous, erect, stipitate; stipe long, slender, purplish brown, flexuous; calyculus variable, sometimes occupying one-third of the sphere, when it is delicately costate, concolorous with the stipe, and pa.s.ses over to the net by a distinctly toothed or serrulate margin, sometimes represented by irregular ribs or costae only; net well differentiated, the threads delicate, transparent, yellow, connecting large black nodules, running from one to the other in pairs or sometimes three together, free ends not numerous, the meshes few-sided, often triangular; spores in ma.s.s, dull olivaceous, under the lens pallid, nearly smooth, 6-7 .

A very rare species, if indeed it occur in this country. At least the form figured by Rostafinski, Tab. II., Fig. 27, and Ma.s.see, Pl. 1, Fig.

11, has not come to our notice. The parallelism of the net threads is a touch added by Rostafinski; Schrader does not mention it. Lister makes this species include the preceding. The form described in _Bull. Lab.

Nat. Hist. Ia._ II., p. 119, is _C. dictydioides_.

Reported from New York, New England and Pennsylvania.

In the English _Monograph_ we are repeatedly a.s.sured that this species is common in the United States. The statement is made possible only by the inclusion of the form originally described from America and truly abundant east of the Rocky Mountains, _C. dictydioides_ Cke. & Balf.; _C. intricata_, by all accounts, just as preeminently the species of Europe. It is true that Schrader did not emphasize the parallel connecting threads by which later authorities distinguish the form; he had little occasion so to do, even did his figures intend accuracy in each detail, which they did not, and Rostafinski's, though his drawing is a diagram, certainly knew what he was doing. Cooke, in his list for Great Britain, quotes the Polish text without dissent, and Ma.s.see follows and ill.u.s.trates; so that there can be no doubt as to what the European species is.

In any cribraria the presence or relative obsolesence, of the calyculus is of little taxonomic import since that structure is variable in every species. In the latest edition of Mr. Lister's work, the American form is entered as a variety in "hot-houses"; apparently advent.i.tious; it is indeed related to the European form but is a geographic species.

9. CRIBRARIA PIRIFORMIS _Schrader._

PLATE XVII., Fig. 9; PLATE XIX., Fig. 9.

1797. _Cribraria piriformis_ Schrad., _Nov. Gen. Pl._, p. 4.

Sporangia gregarious, small, .3-.5 mm., turbinate or globose, erect, purplish brown, stipitate; stipe comparatively short, tapering upward, longitudinally furrowed, purple or brown; calyculus very well defined, about one-third the sporangium, not ribbed, flattened or even umbilicate below, the margin plainly denticulate, dusky brown; the net simple, the meshes large, triangular, with few free ends; the nodules small, globose or undifferentiated, slightly convex or flat; spore ma.s.s dull, yellowish brown; spores by transmitted light pale ochraceous or salmon-tinted, nearly smooth, 5-6 .

Schrader defined this beautiful form chiefly by its shape. This, though variable, is yet generally so far pyriform as to show distinct contraction toward the stipe. The well-defined calyculus is narrowed below and eroded or denticulate above. The cyanic tints due to the presence on the calyculus of radiating lines of purplish granules about one-half the size of the spores, the net open, uniform, the stipe rather stout, short, and distinctly furrowed, rising often from a small hypothallus--these are marks of this species. The net suggests _C.

tenella_, but the latter species is much smaller, has a different stem, much longer and unfurrowed. The cup here is more nearly that of some form of _C. intricata_, but is better defined, pa.s.sing into the net very abruptly by the simple intervention of projecting teeth.

Apparently rare. Our specimens are from New York, through the courtesy of Dr. Rex, Virginia, North Carolina, Iowa, Oregon, Colorado, and represent, as usual a modification of the European type, _C. notabilis_ Rex. Miss Lister, _Mon., 2nd ed._, writes var. _notabilis_.

Colorado forms are remarkable for dense brown coloration.

10. CRIBRARIA TENELLA _Schrader._

PLATE XVII., Fig. 5.