124 NORTH AMERICAN FLORA [VotumgE 15 
18. Dicranum Miihlenbeckii B. S. G. Bryol. Eur. (37-40): 
Dicranum 38. 1847. 
Dicranum Rauei Aust. Bot. Bull. [Bot. Gaz.] 1:28. 1876. 
Dioicous: male plants on tomentum of the fertile stems, 1-4 mm. high with 1 or rarely 2 
flowers, each containing 4-6 antheridia with about twice as many paraphyses, the perigonial 
leaves from an enlarged base rather gradually narrowed to a stout, costate point, serrulate 
above: fertile plants in extensive, compact, mostly yellowish-green mats, with tomentose stems 
up to 7 cm. high or more: stem-leaves 4~6 mm. long, mostly erect-spreading all round, rarely 
falcate-secund, with the point incurved, crispate, or variously bent and twisted when dry, 
nearly erect when moist, from a lanceolate base gradually narrowed to a subtubulose, stout, 
serrulate to nearly entire, acute point; costa vanishing or short-excurrent, about 125 » wide at 
the base and one fifth the width of the leaf-base, from nearly smooth on the back to serrulate one 
half down, in cross-section near the middle of the leaf showing 8-10 guide-cells with stereid- 
bands above and below and a row of medium-sized cells next the ventral and dorsal surfaces; 
alar cells reddish-brown, reaching almost to the costa, those just above short-rectangular, 
12-16 » wide and 40-60 w long with thin, slightly pitted walls, soon becoming shorter upward 
with somewhat thickened not pitted walls, the angular mostly square or slightly elongate cells, 
about 10 y» wide, extending from one fourth or one third up the leaf to near the apex; leaf- 
blade on the back mostly smooth to near the apex, sometimes rough one half down; inner 
perichaetial leaves variable, almost truncate with a short apiculus or rather gradually narrowed 
to a slender, serrulate point two thirds the lower part in length: seta solitary, yellowish, 
mostly 2-2.5 cm. long: capsule cylindric, nearly straight and erect or usually somewhat 
nodding and curved, up to 4 mm. long, its length 4-6 times its diameter, when dry contracted 
under the mouth and furrowed or nearly smooth, not strumose; lid with its obliquely rostrate 
beak scarcely as long as the capsule; peristome-teeth dark, reddish-brown, vertically striate, 
divided more than one half down, 80-100 u wide at the base; annulus distinct, of about 2 rows 
of cells: spores slightly rough, 20-24 u in diameter. 
Type Locauity: Europe. 
DistTRIBsUTION: New England; Ontario to Alaska, and southward to New Jersey and New Mexico; 
also in Europe and Asia. 
ILLUSTRATION: B.S.G. Bryol. Eur. pl. 78. 
Exsicc.: Sull. & Lesq. Musci Bor. Am. 65; ed. 2. 81; Macoun, Can. Musci 38, 57. 
This species is especially known by its long, narrowly cylindric capsule and its broad and short 
lower leaf-cells with scarcely thickened and slightly pitted or not pitted walls, the upper cells be- 
coming nearly square. It has been confused in both Europe and this country with D. Bergeri, a 
species which has much narrower, thicker-walled, more pitted cells, as in Husnot, Musci Galliae 
409, which is evidently in part a small form of D. Bergeri. It bas also been confused with D. fus- 
cescens, which has a shorter capsule, narrower leaf-point, and smaller cells, and even with smaller 
forms of D. Drummondi, when sterile, in which the lower leaf-cells are narrower and the upper ones 
smaller, scarcely in distinct rows, with thin walls. 
19. Dicranum brevifolium Lindb. Musci Scand. 24. 1879. 
Dicranum Miihlenbeckii brevifolium Lindb. Bot. Not. 1865: 80. 1865. 
Dioicous: male plants minute, on tomentum of the fertile stems, the perigonial leaves 
costate, of uniform color to the base, more or less abruptly narrowed to the serrulate apex: 
fertile plants in compact, yellowish-green or brownish tufts, with tomentose stems up to 5 cm. 
high: stem-leaves 4-6 mm. long, mostly erect-spreading all round with the point incurved or 
variously curved or crispate when dry, from a lanceolate base gradually narrowed to a sub- 
tubulose, stout, serrulate to nearly entire, acute point; costa mostly percurrent or slightly 
excurrent, usually nearly smooth on the back, about one fourth the width of the leaf just above 
the base and 125 u wide, in cross-section near the middle showing 8 or 9 guide-cells with stereid- 
bands above and below without differentiated outer cells; alar cells reddish-brown, reaching 
almost to the costa, those just above rectangular, mostly 8-10 » wide and 40-60 » long with 
somewhat thickened, pitted walls, those next above abruptly shorter, with uniformly thickened 
not pitted walls, extending to near the apex, the median cells mostly about 8 » wide, often 
quite irregular, from scarcely elongate to twice as long as wide; leaf-blade on the back mostly 
quite smooth; inner perichaetial leaves abruptly narrowed to a nearly smooth point one third 
to two thirds the broader part in length: seta solitary, yellowish, 1.5-2.5 cm. high: capsule 
