116 NORTH AMERICAN FLORA [VoLuME 15 
ovate-lanceolate base gradually narrowed to a long flexuous point, slightly crenate on the 
incurved margin above; costa of homogeneous cells, often weak below, 25-40 » wide, one sixth 
to one eighth the width of the leaf-base and rather long excurrent; leaf-cells in the upper part 
of the blade with thickened walls, rectangular, about 6 w wide and 20-30 uw long, becoming 
much shorter and broader just above the colored, sometimes inflated, often not very distinct 
alar cells; inner perichaetial leaves ra. her faintly nerved below, longer than the stem-leaves, 
up to 4 mm. long, from a loosely clasping, involute base rather gradually narrowed to a not 
quite entire point shorter than the clasping part: seta stout, erect, about 3 mm. long: capsule 
short, scarcely projecting above the leaves, with a broad mouth, in diameter nearly equaling 
the height of capsule; exothecal cells with rather uniformly thickened walls, the median ones 
about 204 by 30-50 uw; stomata in mostly one row near the base of the spore-sac, about 25 u by 
30 4; annulus compound; peristome-teeth 80 « wide at the base, mostly divided more than 
one half down, vertically striate; lid convex, with a short oblique beak, its height about equal 
to its basal diameter: spores not quite smooth, up to 20 uv in diameter. 
TYPE Locality: Lapland. 
DISTRIBUTION: Port Wells, jaa also in northern Europe. 
ILLUSTRATION: Flora 42: pl. 7 
3. Dicranum fulvellum (Dicks.) Smith, Fl. Brit. 1209. 1804. 
Bryum fulvellum Dicks. Pl. Cryp. Brit. 4:10. 1801. 
Autoicous: male flower on a more or less distinct branch below the perichaetium: plants 
in compact, usually dark tufts, with branching stems 2-3 em. high: leaves usually falcate- 
secund, sometimes erect-flexuous; stem-leaves 2-3 mm. long, from an ovate-lanceolate base 
gradually narrowed to a slender, flexuous, distinctly roughened point, denticulate at the apex; 
costa excurrent, 40-60 » wide at the base and one sixth the width of the leaf-base; leaf-cells 
with somewhat thickened walls, those in the narrow upper part of the blade about 8 » wide 
and 16-25 yu long, those toward the base within often longer and narrower, with the alar 
cells reddish, more or less inflated, forming a rather distinct group and the cells just above 
rather broad and short; perichaetial leaves 5—6 mm. long, from a loosely clasping base gradually 
narrowed to a rough, flexuous point rather longer than the basal part, with the leaf-cells longer 
and narrower above than in the stem-leaves and the cell-walls sometimes slightly pitted: seta 
yellowish, stout, about 4mm. high: capsule short-oblong, nearly or quite erect and symmetric, 
about 1 mm. high and 0.6 mm. through, not reaching to the tips of the leaves, distinctly 
furrowed when dry; lid convex, obliquely short-rostrate; exothecal cells with thickened walls, 
mostly irregularly elongate, the median ones 15-204 wide and up to 504 long; stomata 
mostly few and scattered over the short neck; annulus compound, narrow; peristome-teeth 
about 75 » wide at the base, undivided above, more or less slit near the middle, or sometimes 
divided into irregular forks, with the joints of the inner plates rather indistinct and close to- 
gether, 10-12 4 apart: calyptra rough above: spores roughish, up to 24 uw in diameter. 
TyrE Locality: Ben More, Scotland. : ; 
DistRiBUTION New Hampshire; Northern New York; Yukon; also in Europe and Asia. 
4, Dicranum falcatum Hedw. Sp. Muse. 150. 1801. 
Autoicous: male flower at the base of the perichaetium or sometimes at the apex of a 
branch; plants in compact tufts, green above, brown or blackish within, with more or less 
radiculose, branching stems up to 4 cm. high: leaves falcate-secund, lanceolate-attenuate, 
subtubulose, those on the upper part of the stem 3.5-4 mm. long, with margins not quite entire 
and a point rough with coarse papillae; costa mostly long excurrent, of homogeneous cells, 
about 50 » wide at the base, one fifth to one seventh the width of the leaf-base; leaf-cells with 
slightly thickened, not pitted walls, those in the upper part of the blade angular, short, about 
6 p by 6-12 pw, those below towards the costa up to 50 w long, the nearly square or inflated alar 
cells forming usually a distinct, reddish group, with the cells just above square, smaller; peri- 
chaetial leaves about the length of the stem-leaves, from an ovate, convolute base rather 
gradually narrowed to the rough point: seta yellowish or brown, 8-12 mm. high: capsule 1-1.5 
mm. long, ovate, nodding, slightly curved, strumose, smooth; exothecal cells with somewhat 
unequally thickened walls, varying from slightly elongate to 3-4 times as long as broad with 
