Sporangia more or less closely gregarious, yellowish brown, pear-shaped or obovate, large, .8–1 mm. in diameter, stipitate; stipe brown furrowed, erect or often nodding, about equal to the sporangium or longer; calyculus distinct, marked by numerous dark brown radiating ribs, iridescent, perforate above, deeply dentate, and merging gradually into the elegant network, of which the dark nodes are more distinctly expanded about half way up, less so at the apex and below, the filaments exceedingly delicate, simple, with occasional free ends projecting into the small meshes; spore-mass yellowish, spores by transmitted light almost colorless, minutely roughened, 5–6 µ.

Perhaps the most striking characteristic of the present species, aside from its large size, is the peculiarly perforated cup or calyculus. Schrader's artist failed him here completely. The structure is exceedingly delicate, the peridium between the ribs and reticulations reduced to the last degree of tenuity, with the iridescence of the soap-bubble, here and there lapsed entirely. Withal the structure seems firm enough and persists until all the spores are dissipated by the wind.

Easily distinguished from the preceding, its only rival in size, by the obovate or turbinate, netted sporangium, its much longer stem, and flat, perfectly formed nodes.

Rare. New York, North Carolina, South Carolina, Oregon; Toronto, Canada.

3. Cribraria minutissima Schweinitz.

[Plate XVII]., Figs. 6, 6 a.

Sporangia scattered, orange or nut-brown, very minute, .1–.3 mm. or less, globose or ellipsoidal, stipitate, erect or nodding; hypothallus none; stipe short, 1–3 times the sporangium, filiform, tapering upward, brown; the calyculus variable, sometimes well marked and separated from the net when fully mature, by a shallow constriction, more commonly small or entirely wanting, especially in the spherical sporangia; net simple, large meshed, without nodal expansions, the threads flattened; spore-mass yellow, spores by transmitted light, pale, nearly smooth, 5–6 µ.

A most beautiful tiny species. Generally in all the specimens before us, a perfect, spherical net, firm enough to retain its place and structure after all the spores have been scattered. When mature the spore-mass seems to roll about as a ball, freely within the net, the spores being thus gradually dispersed. The calyculus when present is without veins. 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.