28 BRITISH HEPATIC^. 



jecting backwards, obliquely sub-reniform, very concave, verti 

 appressed, glossy, the margins of opposite leaves meeting, 

 rior border remarkably narrow and decurrent, posterior abri 

 rounded, deflexed ; amphigastria long, subulate. Er. ? 



Addanthus Carringtoni, Balfour, Carring. in Trans. Bot. Soc. Ed. v. x. p. 378 ( 

 Jung, compressa, Herb. Ureville. 

 Alicularia occlusa, Dr. Striton's MSS. 



Hab. This fine species was first recognized as distinct by Br. Striton, of Gli 

 ■who collected it on Ben Lawers, July 1866, and Ben Voirlich, 1869 ! 



It is probably not unfrequent in the Scottish Highlands, whence I had pre^ 

 received specimens labelled J. compressa, from rocks above Loch Avon, Aug. 

 Dr. Greville! and from Mr. A. Croall, July 1856 ! Loch Mar6e Boss, July 

 Mr. G. Howie 1 



It seems to prefer wet, boggy places, forming extensive patches, either ah 

 associated with J. Donniana, J. orcadensis, Bazzania tricreiiata, &c. Only barren 

 have hitherto been met with. 



Stems slender, rigid, flexuose, of a brownisli colour, and ( 

 texture, for the most part naked, but bearing a few scanty > 

 rootlets at the bases of amphigastria, and on the creeping sh 

 Flagella few in number, arising from the ventral aspect oj 

 stems, either naked or clothed with very minute entire lea 

 Barren shoots (f. 31, 1) 2 to 4 inches high, by a line in w 

 simple, or producing occasional innovations from the axill 

 amphigastria, or the summit of old shoots, laterally compre 

 the apex a little recurved. 



Leaves of nearly uniform size, a little smaller and more di 

 at the base, sub-vertically imbricated, appressed, coarctate, 

 ■Ys" to ■^" in diameter, obliquely orbicular or reniform (f. 31, ' 

 entire or obscurely truncate at the apex, very concave, so tha 

 margins of opposite leaves touch before and behind, two-thir 

 the surface projecting posteriorly (f. 31, 2), the ventral b( 

 rounded and inserted at right angles to the stem ; anterior b( 

 remarkably narrow and decurrent (f. 31, 4). 



The texture is firm, membranous, sub-pellucid, altering 

 when dry. Colour uniform, stramineous, or pale olive-g 

 laevigate. 



Areolation ' guttate,' the walls very thick, each larger 

 seeming to be surrounded by a row of smaller ones, ' the inters 

 trigones ' of authors ; but on the application of a drop or ti 

 strong sulphuric acid, or the reagents previously mentioned 

 cells are resolved into clear hexagons (f. 31, 7), separated 

 each other by a pellucid line, and the trigones are seen to cc 

 of three portions, each occupying the corner of a contiguous 

 Marginal cells smaller, sub-quadrate, tiws" by t7Vo"j those c 

 intermediate portion hexagonal, ttbV to t^t" ^ach way. '. 

 cells elongated, ■^" to sh", by tts^" to ^". Trigones verj 



