98 dicranacejE. 



Hab. Heaths and rocky ground ; rare. Fruit only known in Portugal. 



C. introflexus is easily known from all the other species except C. brevipilus by 

 the characters italicised above ; indeed the colour and the hair-points alone serve to 

 distinguish it at first sight ; the sudden transition from the hyaline to the chlorophyllose 

 cells in an obliquely ascending line is very noticeable ; this is however more or less 

 shared by the next species, which in other respects also is somewhat difficult at first 

 to separate. The hair-points in the present plant are usually longer and more 

 conspicuous, — in the dry state by the imbrication of the leaves they are collected into 

 a very distinct penicillate tuft at the top of the stem, — the margin is not recurved in 

 the upper part, the cells are shorter and hardly sinuose, and the deeply furrowed 

 ' nerve is distinctive. In winter, when the young leaves are hardly mature, the hair- 

 points are sometimes very inconspicuous, but are later on developed. 



The leaves are broader, shorter, and more rigid than in most of the species, and 

 the aspect of the plant when dry, and especially the male plant, is not unlike that of 

 Polytrichum pittferum. 



An allied species, C. adustus De Not., resembles dwarf plants of C. atrovirens, 

 but has a narrower nerve, J width of leaf-base, and shorter cells. Specimens 

 gathered in the Channel Is. have been referred to this species, but they are by 

 Braithwaite considered to be a form of C. atrovirens. 



9. Oampylopus brevipilus B. & S. (Tab. XVI. I.). 



A variable plant in size and colour, 1-3 inches high, usually 

 pale ; resembling C. flexuosus var. uliginosus, but with less 

 flexuose leaves when dry ; stems easily separable, slender, leaves 

 usually rather loosely set, sometimes interruptedly tufted. Leaves 

 subulate from a lanceolate base, rather narrow, margin involute, 

 towards the summit very narrowly recurved faintly denticulate 

 above, at apex with a toothed point which is usually slightly 

 elongate and hyaline ; nerve rather narrow, ]4 width of base or 

 less, in section of 3-5 rows of cells, the larger thin-walled series 

 occupying the middle of the nerve, instead of the anterior part as 

 in all the other species ; not grooved at back, very slightly 

 denticulate at back above. Angular cells very variable, hardly 

 distinct, or forming distinct auricles ; cells pale, the basal 

 rectangular, passing into the chlorophyllose as in the last, but 

 less abruptly ; upper cells longer than in that species, narrowly 

 linear -rhomboid or elliptical with a sigmoid curve ; the marginal 

 very narrow. Fruit unknown. Perichaetial bracts with the 

 margin recurved. 



Var. /3. auriculatus Ferg. Auricles enlarged, very distinct. 



Hab. Moist heaths and bogs. Not unfrequent. The var. /3 less common. 



A very variable species in size and habit, and also in the development of the 

 auricles and of the hair-points ; the latter may be altogether wanting, and every form 

 of transition may be found between the var. auriculatus and the forms with the 

 auricles scarcely traceable. The areolation is however distinctive, and taken with the 

 narrow nerve and the usual presence of the hair-point, will afford a pretty certain 

 means of determining the plant ; the recurved margin in the upper part is also 

 characteristic, but is sometimes very slight and inconspicuous. Occasionally, in drier 

 spots, the hair-points become elongated and the plant then simulates C. introflexus. 



