644 Proceedings of the Royal Irish Academy. 



Jimgermaniiia spinulosa, Dicks. Crypt., fasc. 2, p. 14; Hook. Brit.. 



Jung. t. 14; Engl. Bot. t. 2228; Taylor, Fl. Hib. 2, p. 58. 



Plagiochila spinulosa, Dumort. Eev. Jung. p. 13, p. 15, et 



Hepat. Europ. p. 44 ; Lindenb. Sp. Hep. p. 6, t. 1 ; G.L. et N. 



Synop. Hepat. p. 25 ; Carring. Brit. Hepat. p. 59, pi. 4, fig. 14. 



Martinellius spinulosus, B. Gray, in Gray's Nat. Arr. Brit. PI. 692. 

 Hab. "Woods and moist banks. This common species extends over the 



whole of Ireland, and is of frequent occurrence. 



Var. y. Carring. Brit. Hepat. p. 60. Glengarriff and Cromaglaun,. 

 Dr. Carrington. 



3. Plagiochila punctata, Taylor. Dioecious. Stems closely tufted, of 

 a yellowish-green colour. Leaves variable in size and shape, 

 rigid, and very caducous, especially after drying, those on the- 

 main shoots broadly ovate, convex, decurrent, upper margin and 

 apex a little recurved, fringed with spinose teeth. On the ulti- 

 mate branches the leaves are narrower, scarcely wider than the 

 stem, cuneiform and spreading, their margins beset with from 

 two to five distant teeth. Cells largely collenchymatous, very 

 smooth, punctate — Dr. Taylor describes their appearance, " as 

 if coarsely powdered;" Lindberg, as " verrucolosis striatulis." 

 Colesule broadly ovate, from a narrow base, compressed at length, 

 cleft at side, mouth open, beset with long spinulose teeth, 



Plagiochila punctata, Taylor, in London Journal of Bot. 1844, p. 371 

 (sub. n. 10), et 1846, p. 261 ; Trans. Bot. Soc. Edinb., p. 179;. 

 G. L. et N. Synop. Hep. p. 626 ; Dumort. Hep. Eur. p. 45, n. 

 7; Gottsche et Rabenhor. Hep. Eur. exsic. n. 211 ; Lindb. in 

 Acta Societatis Scientiarum Fennicae, x., p. 524. Plagiochila 

 spinulosa, /?. punctata, Carring. Irish Crypt, p. 19, t. 2, f. 3 

 (1863), et Brit. Hepat. part 3, p. 60. 



Hab. Shady woods, and banks among heath. Abundant in the Co. 

 Kerry, especially in the Killarney woods, but not common in the 

 northern or eastern counties. Altadore glen, and at Seven 

 Churches, Wicklow ; Glenad, Co. Leitrim. 



It will be seen from the authors quoted, that considerable diversity of 

 opinion exists as to the right of this plant to rank as a distinct 

 species. Dumortier and Lindberg hold it to be a species, while 

 Carrington considers it only as a variety of P. spinulosa. I have 

 long known its habit, and have collected it in widely different 

 habitats, where the principal characters have been constant. I 

 have sometimes considered it nearer to P. tridenticulata than to 

 P. spinulosa. 



4. Plagiochila tridenticulata, Taylor. Stems decumbent, ascending at 

 apex, flexuose, slightly branched. Leaves distant, wedge-shaped, 

 two to three times toothed at apex. Andi-oecium spicate. 



Jungermannia spinulosa, ^. tridenticulata. Hook. Brit. Jung. p. 9, t. 

 14; Taylor, in El. Hib. 2, p. 58, n. 10, var. minuta. Plagio- 



