208 TORTULACE^I. 



rectangular, hyaline. Seta yellow, longer than in the last species ; 

 capsule oval, equal or slightly asymmetrical, brown, paler when 

 empty, mouth very small, the orifice closed with a membrane , 

 finally rupturing in the centre ; lid obliquely rostellate, variable 

 in length, but longer than in the last species. Spores 18-20 /* in 

 diameter. 



Var. p. obliqua C. M. (Hymenostomum obliquum Nees & 

 Hornsch.). Shorter. Seta shorter; capsule asymmetric, slightly 

 curved above, lid shorter, narrowly conical. 



Var. y. elata (Hymenostomum microstomum var. elatum B. 

 & S.). Taller, densely tufted ; capsule very small ', hardly reach- 

 ing above the elongated innovations. 



Hab. Banks and barren ground, frequent. The var. 0, Ingleton ; the var. y, 

 near Settle, barren. Fr. spring. 



Quite inseparable from W. viridula except by the fruit, which in that has a wider 

 mouth, not closed by a membrane, and presenting some traces, however indistinct, of 

 a peristome. The incurved margins distinguish it from W. squarrosa, the much 

 thinner, more pellucid and delicate leaves, more tapering, and with thinner nerve, 

 from IV. tortilis. 



I have gathered a plant at the Quiraing, Skye, in 1893, which may be referable 

 to the var. elata, though perhaps it is rather an intermediate form ; some of the 

 capsules being concealed by the innovations, but others being distinctly exserted. In 

 the barren state it can hardly be separated from W. viridula var. densifolia. 



7. Weisia tortilis CM. {Gymnostomum tortile Schwgr. ; 



Hymenost. tortile B. & S., Schp. Syn. ; Mollia tortilis 



Braithw., Br. M. Fl.) (Tab. XXX. M.). 



More robust, more branched, bright or dull green above, 

 reddish below. Leaves crowded, wider than in the last, narrowly 

 oblong-lanceolate, broadly pointed; margin widely incurved; 

 nerve very stout, yellow or reddish, excurrent in a short mucro ; 

 cells at base rectangular, hyaline, passing rather abruptly and 

 obliquely into the small, chlorophyllose, very opaque, smaller 

 upper areolation. Capsule resembling that of IV. microstoma, 

 but rather larger, with a rather longer lid and slightly wider 

 mouth. Spores smaller, 12-15 f- 



Hab. Calcareous rocks, banks, and walls. Blare. Fr. spring. 



If due attention be paid to the characters italicised in the above description, there 

 need not be much difficulty in recognising this species, for which forms of W. 

 microstoma and W. viridula are frequently mistaken. It is a distinctly less delicate 

 plant, with the leaves of a very opaque, solid texture, the borders more widely 

 incurved, and the nerve much stronger and reddish ; the whole plant, too, is usually 

 of a lurid tint. In the var. subcylindrica Schp. , to which according to Wilson most 

 of the British specimens belong, the leaves are longer and narrower than in the type, 

 in which state, according to Boulay, it presents no differences from W. crispata CM. 



