Not uncommon. Maine, Iowa, Missouri, Nebraska.
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_.
_A._ Mature capillitium loosely adhering to the calyculus.
_a._ Mature capillitium far-expanded, drooping.
OO Shorter, about 6 mm. 2. _A. oerstedtii_
_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_
_c._ Sporangia yellow 11. _A. pomiformis_
_d._ Sporangia rose-colored, .5-1.5 mm. 12. _A. insignis_
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 papillæ, 7-8 µ.