NEW AND RARE SCOTTISH MOSSES 107 



straight when moist, with slightly undulating margins, crisped when 

 dry, margin narrowly recurved, especially on one side, for nearly the 

 lower half; nerve usually red below, narrow, '045 mm. broad near 

 base, a little broader near middle, then narrowing upwards, prominent 

 behind, ceasing considerably below the acuminated, rather slender 

 apex by as much as '25 to "35 mm., leaves of stems bearing 

 propagula, having the nerve proceeding more nearly to the apex ; 

 propagula longer than in U. phyllantha, mostly with 6 to 7 septa 

 instead of 3 to 5 septa, and dimensions reaching '14 by '036 mm., 

 but falling off much more readily; central basal cells long, narrow, 

 022--034 by -oo4-'oo6 mm. ; outwards shorter and broader, and 

 near margin oblong, 'o^'diS by '007 mm. ; upwards from oblong 

 becoming rounded, with clear spaces between, -oo8-'oi2 diameter; 

 no basal marginal row of pellucid cells as in B. phyllantha. The 

 cells of this species are accordingly larger than those of the other, 

 and more strongly papillose on both sides, papillae generally bi- 

 geminate ; base of leaf and nerve red. Near Arisaig, on branches 

 of trees. 



ISOTHECIUM PERSIMILE. Similar to Is. myunim as regards 

 ramification, etc., but smaller, while the stolons issue, for much the 

 greater part, from the tips of the branches, or rather seem a con- 

 tinuation of them, a few, however, are seen beneath ; both stem and 

 branch leaves bipartite-imbricated, secund or deflexed, oval or nearly 

 elliptical, symmetrical, nerveless, concave especially transversely, 

 margin plane throughout, slightly serrulate above and convex in 

 outline, apex bluntish ; cells in centre of leaf, narrowly linear with 

 blunt extremities, separate and distinct, '03--04 by -oo3- - oo4 mm., 

 outwards a little broader in all directions, especially towards margins, 

 where there is often a marginal row of narrowly oval cells, 'o^-'oiy 

 by 'oo t; mm. ; at alar base a largish group of obtusely quadrate, yellow 

 or reddish, opaque and granular cells, 'OI--OI6 mm. diameter, in 

 four or five perpendicular rows ; branch leaves narrower than, but 

 nearly of the same shape as, the stem leaves, and alar spaces smaller 

 with cells not so deeply coloured, often only yellowish. Ben Sleoch, 

 Loch Maree, 1870. 



There is only one oval capsule with yellow outer teeth, set nearly 

 straight on a strong, smooth, red seta. I refrain from saying more, 

 as the seta is detached from the perichaetium. 



Besides those described several rare or comparatively rare 

 mosses were secured in the neighbourhood of Arisaig, during July 

 and August 1904. Gymnostomum calcareiim, Dicranella ciirvata 

 (Hedw.), Campylopus Shawii (Wils. ) the last in one patch only ; and 

 although I searched diligently for several days, as well as at various 

 times during my stay in the district, I failed to alight upon any more. 

 The nearest station for this moss to the present one is on the east 



