8 BRITISH HEPATIC^. 



Hab. Very rare, or overlooked as a form of G. concinnatum. Found among 

 duplicates of the latter in Dr. GremlMs Herbarium ; collected on Ben Nevis and the 

 Sutherland mountains, 1830 ! Lochnagar, A. GroaU, July, 1856 ! 



It occurs sparingly in Sweden (Funok), Styria {Wehoitsch), Finland {Dr. Livdh&rg), 

 and Lapland [Angstrom). 



EesemUing the last species in habit, but more strikingly jula- 

 ceous and compressed. Stems (f. 4, 2) ascending, rigid, irregularly- 

 branched ; fertile shoots tumid and obtuse at the apex, strongly- 

 compressed, the remainder lanceolate or scimitar- shaped, pointed, 

 but presenting a stunted or deformed appearance from the sudden 

 recurvation of the apex ; sometimes attenuate or interrupted. In 

 colour and habit bearing a close resemblance to stunted forms of 

 Sphcerophoron coralloides. FlagellcB creeping, entangled, dark- 

 brown, clothed sparingly with delicate flax-coloured rootlets, which 

 are seldom found on the erect shoots. 



Leaves (f. 3, 5) so closely imbricated that their outline is made 

 out with diflficulty even under the lens, and so brittle in texture 

 that an entire specimen is rarely obtainable. Form broadly ovate, 

 obtuse, very concave, amplexicaul, bluntly and irregularly emar- 

 gtaate, sometimes almost entire, at others appearing erose or 

 crenulate from fracture of the brittle scariose border, or the out- 

 growth of gonidial cells from it (f. 3, 7). 



Texture thin and fragile. Colour glaucous, silvery-olive. Areo- 

 lation guttulate. The true form of the cells can only be ascer- 

 tained by boiling in water tO' which a few drops of liquor potassse 

 have been added, and then tinting with zinc biniodide. Marginal 

 cells hyaline, subquadrate, xtVo" ^o t"4oo" long, and - ^z^ 3" broad. 

 Those of the centre larger, chlorophyllose, and hexagonal, tooo" 

 by 1 2^ q " * Basal cells mor« elongate, -f}-f" by -ttoo"- Trigones 

 indistinct. Frof. Lindberg states that they are not papillose like 

 those of G. concinnattmi. The borders of the leaves are often 

 obscured by minute pellucid 4- or 5-angular proliferous cells resem- 

 bling the so-called gemmes of many species. 



I)ioicous. Pertile shoots shorter, clavate, or sub-pyriform ; 

 more compressed (f. 2, right-hand fig.). 



Involucral leaves (f. 4, 6) closely imbricated, and scarcely differ- 

 ing from the rest, except in their greater breadth and more obscure 

 emargination. (The second pair has been removed in the drawing 

 (f. 6), so as to show the upper leaves more distinctly.) 



Outer involucral leaves (f. 4, 7) convolute, appressed, broader 

 than long ; margin entire or erose-denticulate, not recurved. Inner 

 involucral leaves two in number, shorter, pellucid ; margin obscurely 

 lobate-dentate, closely embracing each other, and surrounding the 

 sporangium. 



* For the measurement of the leaf-ceUs and spores I am indebted to the kindness 

 of my friend Dr. J. W. Edmond, of Inveresk. 



