BRITISH HEPATIC^.. 65 



Pl. III. Fig. lO.i— p. TEiDENTicuLATA. 1. Slioots naiuTol size, 2. Upper portion 

 of (J shoot X 20. 3, 3, 4. Stem-leaves. 5. 5. Ferigonial leaves. 6. Antheridium. 

 7. Leaf-cells x 250. 8. Amphigasta-ia. 



5. Plagiochila exigtja, Taylor. 



Pl. IV. Fig. 13, 



Stolons filiform, serpentine, decumbent ; shoots laxly csespitose, 

 ascending; leaves few, erecto-patent, distant, ovate-cuneate, plane, 

 from a contracted base ; apex bidentate, the segments and sinus 

 rather acute. 



Jungermannia eaaigua, Tayl. in Trans. Bot. Soc. Ed. i. p. 179. 

 Plagiochila eodgua, Tayl. in Lond. Jour. Bot. v. p. 26,4, n. 14 (1846); G. L. N. 

 Syn. Hepat. p. 659 ; Dumort. Hep. Eur. p. 46, n. 8 (1874). 



Hab. — Epiphytic on tufts of Frullaiiia, Radula, &c. ; on \vet rocks, Knocka- 

 voHila and Dunkerron, Br. S. Taylor, 1840 ! Tore mountain on F. Tamarisci, Sep. 

 1841, Dr. Taijlor. Killarney, 1861 ! Cromagloun, 1865, Br. Moore. Glengariffe, 

 Sep. 1869 ! 



Fronds (f. 13, 1) forming minute scattered or more dense tufts, 

 creeping over the surface of Frullania, &c., and resembling in size 

 Jung, turbinata, or J. cuneifolia. 



Frimary stems creeping, filiform, flexuose, about the thickness 

 of human hair, pale olive or brown, and composed of lax, recti- 

 linear cellules. 



Rootlets (f. 13, 2) short, translucent, produced in a fasciculate 

 manner at intervals from the underside of the creeping stems, and 

 sometimes from the amphigastria of the ascending shoots. 



Shoots very minute, scattered, simple, declinate or ascending, 

 2 to 3 lines in length, by -^" in diameter, naked at the base, the 

 apex compressed and recurved. 



Leaves (f. 13, 3) few, distantly placed, alternate, erecto-patent, 

 sub-vertical, from a very narrow attachment, roundish - ovate, 

 obovate or cuneate ; dorsal margin slightly reflexed ; apex bi- 

 dentate, the sinus acute but shallow (equal to ^th of the length), 

 lobes acute, slightly divergent, upper surface plane. 



Texture tender, laxly reticulate, pellucid, on which account, 

 and because of the narrow insertion, the leaves are easily detached, 

 so that in the dry state only a few of the terminal ones are found 

 adherent, which are compressed and secund (f. IS, 6). Colour pale 

 green or olive. 



Amphigastria (f. 13, 6, 7) generally present, minute, subulate, 

 and toothed on one side, or acutely bidentate. 



Leaf -cells (f. 13, 4, 6) large for the size of the plant, hexagonal, 

 with thick prominent walls, but destitute of angular thickenings. 

 Marginal cells slightly flattened, tttt" X ttto" 5 those of the upper 

 third gy 5" to y^" by xiW '> basal cells y^" to 5^" x xryo"- 



K 



