192 TORTULACE^. 



Leaves spreading and recurved from a more erect whitish ba^e r 

 ■when dry flexnose and slightly curled, the uppermost larger, 

 long, narrowly linear-lanceolate , with a short acute point ; margin 

 widely recurved to near apex, faintly or distinctly and irregularly 

 denticulate at point ; nerve vanishing in the apex or excurrent in 

 a minute apiculus ; cells quadrate, obscure, papillose, at base 

 narrowly elongate-rectangular, pellucid. Perichastial bracts long, 

 sheathing; seta long, red; capsule erect, cylindrical, pale brownish 

 green, reddish brown when old ; annulus distinct, fragile ; lid 

 rostellate, usually very short, oblique ; peristome teeth united at 

 base in a very short membrane, 16, short, pale red, linear, with a 

 median line but rarely divided, nodose at the articulations. 

 Paroicous or synoicous. 



Var. /3. dentata Braithw. (Didymodon rubellus var. dentatus 

 Schp.). Plant taller, leaves longer, margin recurved only to about 

 the middle, strongly dentate above ; lid longer. 



Var. y. ruberrima Braithw. (Didymodon rubellus var, 

 ruberrimus Ferg.). Plants ta'Iler, with very slender branches, 

 all red or only the tips yellowish ; leaves all very short, appressed 

 and slightly twisted when dry, from a widely ovate base shortly 

 acuminate to a stout acute point, mostly formed by the nerve, 

 entire ; lower cells smaller and shorter. 



Hab. Rocks, stony places, walls, etc., most abundant in mountainous regions; 

 very common. The var. on mountain rocks ; the var. y in similar situations, 

 principally near streams and waterfalls. Fr. autumn. 



The specific name is very appropriate, the bright, brick red colour of the lower 

 leaves being almost invariably present and very characteristic ; indeed it may nearly 

 always be relied upon to distinguish the species from allied plants. The fruit too is- 

 distinct and little variable : in the var. dentata the lid is markedly longer, and with 

 the other characters is held by some bryologists to constitute a sufficient specific basis 

 for this plant ; the amount of denticulation in the leaves is, however, greatly variable, 

 and in the same tuft with normal capsules I have occasionally found one or two with 

 the lid no longer than in typical rubella. The antheridia in this variety are rare, and 

 are often quite absent on fertile plants ; I have, however, found them occasionally 

 mixed with the archegonia ; and as, even when they are absent from the lower bracts, 

 numerous paraphyses are constantly found, the suppression of the antheridia is clearly 

 due rather to simple abortion than to any actual difference in the character of the- 

 inflorescence. The var. ruberrima is even more distinct in habit, and, according to 

 my own experience, is extremely rare in fruit ; indeed though I have gathered it in 

 many localities I have never found it fruiting. It is very much like Didymodon rufus 

 Lorentz, but that has larger, wider leaves, with smaller basal cells and narrower nerve.. 



3. Barbula tophacea Mitt. (Trichostomum tophaceum Brid. r 



Schp. Syn. ; B. brevifolia Lindb., Braithw. Br. M. Fl.). 



(Tab. XXIX. C). 



In dense irregular tufts, olive green or brown above, below 

 frequently much encrusted with hard calcareous matter and 



