Part 2, 1913] DICRANACEAE 127 
middle with 7 or 8 guide-cells and stereid-bands above and below of 2 or 3 rows of cells, the 
outer scarcely differentiated; alar cells golden-brown; cells of the lower part of the blade 
elongate, with thickened, pitted walls, the median and upper ones shorter, often scarcely 
elongate, with thickened, not pitted walls; inner perichaetial leaves about the length of the 
stem-leaves, rather abruptly narrowed to a slender, entire point nearly as long as the broader 
part and mostly formed of the excurrent costa: seta 15-18 mm. long, slender, mostly pale- 
reddish: capsule about 1.5 mm. long, slightly nodding, curved, somewhat furrowed when dry, 
the exothecal cells elongate with slightly sinuous, unequally thickened walls, with stomata in 
mostly 1 row near the base; annulus of 2 or 3 rows of cells; lid with the oblique beak about as 
long as the capsule; peristome-teeth dark-red, vertically striate to near the apex, divided two 
thirds down or more, with distinct articulations on the inner face about 20 » apart: spores 
roughish, up to 24 » in diameter. 
TYPE Locality: France. 
DistrrBution: Greenland to Alaska and southward to the mountains of New England and 
Montana; also in Europe and Asia. 
a ae Drummond, Musci Am. 91, 92; Aust. Musci App. 471; Ren. & Card. Musci Am. Sept. 
ES. 
24. Dicranum groenlandicum Brid. Musc. Recent. Suppl. 4: 68. 1819. 
Dicranum labradoricum C. Miill. Syn. 1: 366. 1848. 
Dicranum tenuinerve J. E. Zett. Sv. Vet.-Akad. Handl. II. 13:14, 1876. 
Dicranum Macounii Aust. Bot. Gaz. 2:96. 1877. 
Dioicous: male plants mixed with the fertile and much more slender, with elongate stems 
bearing several scattered, brown buds containing 7 or 8 antheridia about 0.4 mm. long and 
numerous paraphyses, the inner perigonial leaves ecostate, broadly ovate, short-pointed, the 
outer faintly costate, longer-pointed: fertile plants in compact, glossy mostly brownish-green 
tufts, with tomentose stems up to 10 cm. high: stem-leaves 3~4.5 mm. long, lanceolate, subtubu- 
lose, entire or slightly denticulate at the very apex; costa percurrent, the apex rather blunt, a 
little above its base one eighth to one tenth the width of the leaf, in cross-section near the middle 
with about 8 guide-cells and well defined stereid-bands above and below, the outer cells some- 
what differentiated on the dorsal side; alar cells brown, reaching about half way to the costa, 
the cells above to the apex elongate with much thickened walls pitted to above the middle of 
the leaf or to near the apex, the median cells 40-60 w long and 6 « wide; inner perichaetial 
leaves convolute, faintly costate, abruptly narrowed to a smooth, subulate point up to two 
thirds as long as the broader part: seta pale-reddish, up to 2 cm. long: capsule short-cylindric, 
1.5 mm. long, nearly straight and erect, furrowed when dry, with stomata in nearly one row at 
the base; lid with a slender beak, rather longer than the capsule; annulus of 1 or 2 rows of 
cells; peristome-teeth dark-red, vertically striate nearly to the apex: spores rough, up to 20 
in diameter. 
TypE LOCALITY: Greenland. 
DistriBpution: Greenland to Alaska and southward to the mountains of New England; also in 
Europe and Asia. 
ILLUSTRATION: B.S.G. Bryol. Eur. $l. 76. (This plate is called D. elongatum, but more nearly 
represents D. mroeniondicum by both the relatively much narrower costa and the narrower upper leaf- 
cells.) ee pe ee 
Exsice.: Sull. & ‘Lesa. Musci Bor. Am. 63, 79, 
D. groenlandicum is much like D. elongatum, but usually of a browner color, a little more robust, 
with straighter capsule and especially differs in the relatively narrower costa and more elongate upper 
leaf-cells with irregularly thickened walls pitted to well above the middle of the leaf. In D. elongatum 
the cell-walls are pitted only near the leaf-base, the upper leaf-cells often oblong or roundish with 
evenly thickened, not pitted walls. 
> 25. Dicranum majus Smith, Fl. Brit. 1202. 1804. 
“Dioicous: male plants minute, attached to tomentum of the fertile stems, with flowers 
more or less in clusters: fertile plants in rather loose, glossy-green tufts, tomentose within; 
stems up to 10 cm. or more high, with usually falcate-secund leaves (almost straight in var. 
orthophyllum) up to 15 mm. long, from an ovate-lanceolate base gradually narrowed to a sub- 
tubtilose, acute point, dentate on the margins and back about one third down, the teeth toward 
the apex larger, with the acute point often slightly incurved; costa percurrent or excurrent, just 
