FISSIDENS. 1213 



F. Otrii Lindb. (F. tequendamensis Mitt.) must, I think, undoubtedly be 

 excluded as an introduction ; its main feature is the longly excurrent nerve. 



* Fissidens Curnowii Mitt. (F. bryoides var c&spitans Schp., 

 Syn.) (Tab. XX. G.). 



Taller, 1-2 inches, soft, caespitose, often very densely and 

 compactly tufted, bright glaucous green above, pale red or whitish 

 below ; stems clothed with red radicles. Leaves very numerous, 

 rather narrower and often more acute ; the border variable, but, 

 with the nerve, usually strong, white and shining when dry. 

 Capsule small, slightly inclined and unequal, often hidden by the 

 upper leaves of the innovations. 



Hab. Cliffs and caves, principally near the sea ; rare. South-west England ; 

 North Wales. 



Very noticeable in size, colour, and mode of growth, of a more delicate texture 

 than F. bryoides, and with the capsule distinctly asymmetric ; I do not, however, find 

 the other characters sometimes given, as to width of limb, form of leaf, etc., by any 

 means constant. I have also several times found intermediate forms difficult to 

 determine, in the absence of fruit. Mitten places it under the Section with the 

 " male fl. either basal or terminal," but in all the specimens I have examined (some 

 of them plants of Curnow's own gathering and verified by Braithwaite) they are 

 axillary, and no less conspicuous than in F. bryoides. The presence of abundant 

 radicles on the stem is an unusual feature in this genus. 



7. Fissidens rivularis Spruce. (Tab. XX. H.). 



Allied to F. bryoides, but taller, f-i inch high, dull green, 

 not radiculose. Leaves long, crowded, elongate-lingulate, broad 

 at apex or narrowly acute ; border very thick and yellowish, con- 

 tinuous to apex as is also the nerve, which runs out into a point, 

 forming with the borders a stout mucro ; areolation very dense 

 and opaque, distinctly smaller than in F. bryoides, 6-8 fi wide, not 

 incrassate. Capsule on a terminal slender flexuose seta, erect or 

 slightly inclined, symmetrical, similar to that of F. bryoides. Male 

 flowers axillary, as in the latter species. 



Hab. Wet rocks by springs and waterfalls. Very rare. Fairlight Glen, 

 Hastings. Fr. winter. 



A very distinct species, separated from the following ones by the axillary male 

 inflorescence and the minute areolation, from F. bryoides by the more robust habit, 

 the smaller opaque, chlorophyllose cells, and the very thick, solid border. F. Curnowii 

 is a more delicate plant with narrower border and thinner, more pellucid areolation. 

 The strong border and nerve are obvious with a lens, especially in the dry state, but it 

 would be difficult to distinguish F. rivularis in the field from F. rufulus and F. 

 crassipes, except perhaps by the stout rigid mucro of the leaves, which are wanting in 

 the red tinge so often found in those plants. 



According to my experience, the fruit is only just ripe in January. The plant 

 appears to have become destroyed in Holmes' original station, but has turned up in 

 several .other sppts in Fairlight Glen,>oJhat;JortunaJeJy it is not likely to be lost. 



