2l8 TORTULACE/E. 



The remarkable basal areolation common to this and some of the following 

 species amply distinguishes the present from the three foregoing plants, from which 

 the white shining leaf-base will also as a rule distinguish it ; T. nitidum has more 

 fragile leaves, more closely circinate when dry, and more narrowly pointed ; T. 

 inclinatum is on the other hand almost inseparable without the fruit ; but the leaves 

 are usually rather shorter, and less closely incurved when dry. 



I have gathered specimens with tapering, acute points, but they are uncommon. 

 As a rule the wide points with strongly incurved margins are very characteristic. 



4. Trichostomum tenuirostre Lindb. (Weisia tenuirostris 



Hook. & Tayl., Didymodon cylindricus B. & S., Schp. Syn. ; 



Mollia tenuirostris Lindb., Braithw. Br. M. Fl.) 



(Tab. XXXI. K.) 



In loose, soft tufts, J- 3 inches high, almost always yellowish 

 green at least at the tips of the stems, yellowish brown or 

 blackish below ; stems flexuose, slender or robust. Leaves fragile, 

 not densely crowded, spreading and flexuose, when dry crisped, 

 incurved and contorted, but not closely circinate-incurved as in 

 the preceding plants, less shining at back on account of the 

 narrower nerve ; longer than in any of the foregoing species, 

 i}4.-2%. lines in length, ligulate or narrowly linear-lanceolate, 

 usually more tapering at apex, and ending in a slender point ; 

 margin plane, undulate, frequently somewhat sinuose above, 

 notched or irregularly dentate, crenulate with papillae ; nerve 

 rather narrow above, reaching to apex or vanishing ; cells at base 

 rectangular, hyaline, rather wide, thin-walled, gradually and not 

 obliquely passing into the shorter, chlorophyllose cells ; upper 

 areolation roundish-quadrate, larger than in the last, somewhat 

 obscure. Seta slender, yellow, often two from the same 

 pericha^tium ; capsule small, narrowly cylindric, pale brown ; 

 lid conical with a narrow rostellate oblique beak ; peristome teeth 

 short, slender, erect, cleft or perforated, fragile. 



Var. ji. Daldinianum (Didym. cylindricus var. Daldinianus 

 De Not.) Leaves shorter, broader, very acute, gradually taper- 

 ing or suddenly apiculate, with two marginal rows of cells 

 incrassate , yellow, distinct ; capsule smaller. 



Var. y. Holtii (Mollia tenuirostris var. Holtii Braithw.) 

 Robust, deep green above, black below; leaves more crowded, 

 the upper ones sometimes slightly secund, more erect and straight, 

 wide, rather obtuse at apex, cells less papillose. 



Hab. Wet rocks by streams ; not uncommon. The var. J3, in more alpine 

 situations, rare ; the var. 7 by waterfalls on dripping rocks, not common. Fr. very 

 rare, late autumn. 



