Part 217 (1/2)

24. Jungermannia. Involucral leaves few, mostly larger than the entire or bidentate stem-leaves. Medium-sized or large.

[++][++] Underleaves 2--4-cleft, -parted, or -divided.

17. Geocalyx. Involucre fleshy, saccate, pendent. Leaves bidentate; underleaves 2-cleft.

18. Lophocolea. Fruit terminal on the main stem or a primary branch.

Involucral leaves distinct.

19. Chiloscyphus. Fruit on a short lateral branch. Involucral leaves distinct. (See also Jungermannia.)

[++][++][++] Underleaves mostly wanting.

[a.] Leaves entire or barely retuse.

23. Liochlaena. Involucral leaves distinct, like those of the stem; perianth truncate-depressed at the apex.

26. Nardia. Involucral leaves connate at base and adnate to the perianth.

[b.] Leaves bidentate or bilobed, rarely 3-lobed.

12. Cephalozia. Branches all from beneath. Perianth on a short branch, mostly trigonal with the odd angle beneath.

24. Jungermannia. Simple or branching laterally. Perianth terminal, mostly laterally compressed.

[c.] Leaves mostly spinulose or dentate.

20. Plagiochila. Involucral leaves large; perianth laterally compressed.

-- 2. Plant-body pseudo-foliaceous with succubous leaf-like lobes.

28. Fos...o...b..onia. Perianth large, campanulate.

-- 3. Plant-body a thallus.

[*] Thallus with a distinct costa.

29. Pallavicinia. Thallus 3--6” wide, mostly simple, the margins sinuate or undulate. Perianth tubular, at length dorsal.

30. Blasia. Thallus 3--6” wide, lobed, dichotomous, or radiate, the margins pinnatifid-sinuate.

32. Metzgeria. Thallus narrow (1--2”), ciliate at the margins or on one or both sides.

[*][*] Thallus with an inconspicuous costa or none.

33. Aneura. Thallus rather narrow, mostly palmately or pinnately lobed.

Sporogonium rising from the under side near the margin.

31. Pellia. Thallus wider, mostly simple or forked. Sporogonium rising from the upper surface.

1. FRULLaNIA, Raddi. (Pl. 24.)