[*] Monœcious.
1. P. epiphýlla, Raddi. ([Pl. 23.]) Thallus oblong, lobed and sinuate, somewhat fleshy, much thickened in the middle; capsule exserted.—On the ground in wet places; not uncommon eastward. (Eu.)
[*][*] Diœcious.
2. P. endiviæfòlia, Dumort. Thallus flat, green or purplish, broadly linear, dichotomous, the margin mostly undulate or crisped.—On the ground and in ditches; common, but often confused with n. 1. (Eu.)
3. P. calycìna, Nees. Thallus dichotomous, proliferous, the early divisions linear-oblong, the margins ascending and remotely sinuate, the later divisions linear-palmatifid, coarsely nerved; cells large, hexagonal; involucre ciliate-fringed or lacerate; calyptra smooth, included.—Wet limestones and shales. (Eu.)
32. METZGÈRIA, Raddi. ([Pl. 23.])
Thallus linear, dichotomous, with well defined costa. Diœcious. Fructification arising from the under side of the costa. Involucre 1-leaved, scale-like, at length ventricose. Calyptra clavate or pyriform, fleshy. Capsule short-pedicelled. Elaters unispiral, some remaining attached to the tips of the valves. Spores minute, mostly smooth. Antheridia globose, enclosed in a scale on the under surface of the costa. (Named for J. Metzger, a German botanist.)
[*] Densely villous throughout.
1. M. pubéscens, Raddi. Thallus 1–2´ long, 1´´ wide, alternately pinnate or somewhat decompound, the short linear branches of uniform width, flat, the margin undulate; hairs longer beneath, single or in twos and threes near the margin, irregularly curved; midrib nearly without cortical layer, with 6–10 (mostly 8) rows of very uniform peripheral cells; diœcious.—In mountain regions, eastward. (Eu.)
[*][*] Hairy on the margins and midrib beneath, smooth above; diœcious (n. 4 monœcious).