JAMESONIELLA. 287 



Jamesoniella Carringtoni {Balf\ Spruce. 



Adelanthus Carringtoni, Balf. MSS. Carr. in Trans. Bot. Soc. Edin. p. 378 



(1870). 

 Nardia Carringtoni, Carr. Brit. Hep. p. 27 (1874-0). 

 N'ardia comjjreasa, var. Carringtoni, Lindb. in Hep. Hibern. in Act. S )c. Sc, Fenn. 



(1875). 

 Jamesoniella Caii'ingioni (Balf.), Spruce, Journ. of Bot. (187G). 



Dioicous, csespitose, flagelliferous, largish to very large, pale 

 or olive green in colour. Stems procumbent or suberect, simple or 

 innovantly branched, branches postical-lateral, rootlets slender, 

 few, whitish, fasciculate ; firm, flexuose, brownish colour, apex more 

 or less circinnate. Leaves alternate, succubous, laterally appressed, 

 obliquely inserted, secund, very concave, imbricate, regular, lower 

 ones minute, distant, subrotund or cuneate ; obliquely orbicular 

 or reniform, antical base very decurrent, postical semicordate, 

 ampliate, abruptly and very narrowly decurrent, margin entire or 

 furnished with few large teeth, 1-6 ; epidermis polished, texture 

 firm, subpellucid, little altered when dry, cells from very small to 

 medium size, roundish, walls thick, trigones distinct, angles 

 thickened. Stipules absent or rudimentary, towards apex of stem 

 or branches, very minute, sublinear, muchnarrow^er than the stem, 

 appressed ; to about the middle or base unequally or equally 

 divided, segments subulate. Androecia at apex of stem or branch 

 or on lateral branches, spicate, perigonial bracts 6-10 pairs, a 

 little smaller, turgid, antical lobule narrow ; antheridia at base 

 solitary (2-3, Dr. C), spherical, mixed with paraphyses. 



Dimensions. — Stems 2 to 4 inches long, diam. "2 mm., with 

 leaves 1*5 mm. to 175 mm. wide; leaves 1'5 mm, high from the 

 decurrent base x 1"4 mm. broad, 1*3 ram. x 1*3 mm., 1"2 mm. 



X 1*4 mm.; teeth "125 mm. long; cells "035 mm., '03 mm., 

 '0225 mm., "02 mm. ; cell- walls '0075 mm. ; trigones "01 mm. ; 

 stipule 2 mm. long x '05 mm. broad at base; antheridia '14 mm. 



X -12 mm. 



Hab. — Growing on wet rocks and damp rocky ledges in alpine 

 districts in Scotland. Very rare. 



