SUB-TRIBE PTILIDIEÆ.

20. Trichocolea tomentella, Ehrhart, Dumort. Jungermania tomentella, Ehrh. Beitr. 2, p. 150. Hook, Brit. Jung., tab. 36. Hanging in dense tufts over the rocks within the spray of the waterfall.

SUB-TRIBE TRIGONAFTHEE.

21. Lepidozia setacea, Web. Jungermania setacea, Weber. Spicil. Fl. Gott, p. 143. Hook, Brit. Jung., t. 8. On moist banks and decayed wood, common.

22. Bazzania trilobata, Linn. Jungermania trilobata. Hook, Brit. Jung., t. 76. Mastigobryum trilobatum, G. L. et N. Syn. Hep., p. 230. On wet banks and rocks, common.

23. Cephalozia divaricata, Smith, Dumort. Jungermania divaricata, Sm. Eng. Bot., t. 719. On a damp bank, rare.

SUB-TRIBE SCAPANOIDEÆ.

24. Scapania resupinata, Linn. Dumort. Jungermania resupinata, Linn. sp. Pl., 1599. Eng. -Bot., tab. 2437. J. recurvifolia, Hook, Brit. Jung., t. 21, f. 8. Martinellia gracilis, Lindberg, Hepatica in Hib., p. 520. Moore on Irish Hepaticæ, p. 640. On rocks near the waterfall, and on stems of trees near the ground, bearing copious gemmæ. This plant has frequently been mistaken for Scapania nemorosa. It differs from all forms of that species by the leaves being somewhat curved downwards, having smaller cells and smaller teeth on the leaf margins. The following description will enable students to distinguish it. Tufts wide, compact, cushion-like, not easily separated, colour olive-yellow or olive-brown, and sometimes like the Torc waterfall specimens, pale light green; disposed in strata corresponding to each year's growth. The interior of the tufts is of a fawn or dull green colour. Stems 20-90 mm. long, erect, slightly branched, rigid, wavy, the secondary shoots or innovations are densely leafy, slender with a crisped appearance from the downward curving of the leaves. Root-hairs numerous, long, white, issuing from the base of leaves. Leaves of uniform size, spreading, bifarious, closely imbricated, base amplixicaul unequally 2-lobed for or at most their length, more or less ciliately dentate. Lobes folded together in upper

leaves nearly equal; dorsal roundish, blunt or with a small point (apiculate) slightly reflexed; ventral (lobule) one-half the size of the lobe, roundish ovate, concave, crossing the stem. Texture thin but firm, somewhat pellucid, little altered when dry. Cells minute, arranged in concentric circles, especially towards the base of the leaf. Gemmæ mostly the colour of the leaves, sometimes dark reddish, and are then very conspicuous, sphærical, grouped at apex of stem and on the leaf margins, copious.

Diacious. Bracts two, with two nearly equal-toothed lobes. Perianth immersed for one-half its length, wedge-shaped, ovate compressed in the bracts; mouth truncate, irregularly cut and fringed with long close decurved teeth. Capsule, small oval, on a short stalk. Spores, minute sphærical, reddish. 25. Scapania nemorosa, Linn, Dumort. Jungermania nemorosa, Linn. Sp. ed. 3, p. 1598. Hook, Brit. Jung., tab. 28 in part. On damp rocks and banks.

26. Scapania aspera, Müll. Scapania æquiloba, var. dentata, Gottch. Scapania aspera. Pearson in Journal of Bot. Decr., 1892, tab. 329. M'Ardle, Musci and Hepatice of the County Cavan.' On rocks and among mosses on damp banks.

27. Scapania undulata, Linn. Dill. Jungermania undulata, Linn. Sp. Pl. 1598. Hook, Brit. Junger., tab. 22. On wet rocks and moist banks, common.

28. Diplophyllum albicans, Linn. Dumort. Jungermania albicans, Hook, Brit. Jung., t. 23. On rocks and banks about the roots of trees, common.

SUB-TRIBE EPIGONEANTHEÆ.

29. Lophocolea bidentata, Linn., Dumort. Jungermania bidentata, Sm. Eng. Bot., t. 606. On damp banks and on decayed wood,

common.

30. Lophocolea spicata, Taylor in G. L. et N. Synop. Hepat., p. 167. Carr and Pearson Exic., No. 263. On decayed wood and on damp rocks among Hypnum, fertile.

31. Plagiochila asplenioides, Linn., Dumort. Jungermania asplenioides, Linn. Sp. Pl., p. 1597. Hook, Brit Jung., t. 13. On banks and on damp rocks, common.

1 Proc. R. I. Academy, 3rd Series, vol. iv., p. 612, Pl. xxi., 1898.

Plagiochila asplenioides, L. var. devexa, Carr. Brit. Hepat., p. 56.
On damp rocks, rare.

Plagiochila asplenioides, L. var. minor.

Carr., Brit. Hepat., p. 56.

Rare.

Carr and Pearson Exic., No. 88-222.

32. Plagiochila spinulosa, Dicks. Dumort. Jungermania spinulosa, Dicks. Crypt. fasc. 2, p. 14. Hook, Brit. Jung., t. 14. rocks and moist banks, common.

On

Plagiochola spinulosa, Dicks, var. inermis, Carrington, Brit. Hep.,
p. 60.
On moist rocks, rare.

33. Plagiochila punctata, Taylor in Lond. Jour. of Bot., 1844, p. 371. P. spinulosa, var. punctata, Carr., Irish Crypt, p. 19, t. ii., fig. 3, 1863. On damp banks and on rocks among Frullania.

34. Plagiochila tridenticulata, Taylor. Jungermania spinulosa, var. tridenticulata, Hook, Brit. Jung., p. 9, t. 14. On damp rocks among Frullania, rare.

35. Nardia emarginata, Ehrhart, Gray. Jungermania emarginata, Ehrh. Beitr. 3, p. 80. Hook., Brit. Junger., t. 27. On damp rocks,

common.

36. Saccogyna viticulosa, Mich. Dumort. Jungermania viticulosa, Hook, Brit. Jung. t. 60. On damp banks and on rocks among mosses, common.

SUB-TRIBE FOSSOMBRONIEÆ.

37. Pellia epiphylla, Linn, Dill. Jungermania epiphylla, Hook, Brit. Jung., tab. 47, figs. 1, 4, 8, 17. River bank, common.

38. Pellia calycina, Taylor Nees. Jungermania epiphylla, var. furcigera, Hook, Brit. Jung., t. 47, f. 18, et 2, 3, 9, 10, 12. J. calycina, Tayl. in Fl. Hib. 2, p. 55. On wet rocks.

SUB-TRIBE METZGERIEÆ.

39. Metzgeria furcata, Linn. Dumort. Jungermania furcata, Linn., Sp. Pl. 1602. Hook, Brit. Jung., tab. 55, 56. On the trunks of trees and on rocks.

Metzgeria furcata, L. var. fruticulosa, Dicks, Lindberg. Jungermania furcata, var. aruginosa, Hook, Brit. Jung. in textu ad tab. 55, 56. On the trunks of trees.

40. Metzgeria hamata, Lindberg. Jungermania furcata, var. elongata, Hook, Brit. Jung. in textu ad tab. 55 et 56. Lindberg's

Monogr. Metzg., p. 25, fig. 5. On damp rocks which are often submerged, very fine specimens.

41. Metzgeria conjugata, Lindberg, Monogr. Metzg, p. 29, fig. 6. On the trunks of trees and on damp rocks, fertile.

42. Aneura multifida, Linn. Jungermania multifida, Hook, Brit. Jung., t. 45. On damp banks, common.

43. Aneura palmata, Hedwig. Jungermania palmata, Hedw., Theor. Gen. 1 ed., p. 87, tab. 18, figs. 93 et 95. On decayed wood,

rare.

44. Aneura latifrons, Lindberg. Jungermania multifida, Schmid., Icon. Pl. 3, pp. 213–216. 1797. Aneura palmata, var. major, Nees, Europ. Leber. 3, p. 459. On moist banks among mosses, &c.,

rare.

SUB-ORDER 2.-MARCHANTIACEÆ.

45. Conocephalus conicus, Linn, Dumort. Marchantia conica, Eng. Bot., tab. 504. Fegatella conica, G. L. et N. Syn. Hep. 546. On rocks at the waterfall, and on the river bank, common. 46. Lunularia cruciata, Linn, Dumort. Lunularia vulgaris, Micheli, Nov. Gen. 4, t. 4. Wall at the entrance to the glen which leads to the waterfall, common.

47. Dumortiera hirsuta, Swartz, var. irrigua, Taylor, sps. Hygrophylla irrigua, Taylor de March. in Linn. Trans. xvii., p. 390, tab. 15, f. 1. In the sheltered rocky recesses of the waterfall, plentiful, rare.

R.I.A. PROC., SER. III., VOL. V.

2 A

3. Portion of plant bearing perianths. x 8.

4. One of the amentæ, showing the antheridia in the saccate base of the altered leaves.

× 20.

5. Involucral leaves with oval rotundate lobules. Perianth, calyptra and capsule. x 20.

6. Leaf. × 30.

7. Leaf showing lobule, which is half or more the breadth of the superior lobe with which it forms a sharp angle, and upon which it lies flat. × 30.

8. Portion of a leaf showing cells.

× 250.

2. The same (x 20), showing the inversely cone-shaped or trumpetshaped perianth, branching and leaves with rounded decurrent lobules,th the size of the lobe which is sharply divergent from the fold of the lobule (the latter character is unique among European species of Radula).