208 WILLIAMS: THE GENUS DESMATODON 
differentiated. Cells of upper part of leaf mostly quadrate to 
hexagonal, scarcely or not elongate, obscure, densely papillose on 
both sides or distinct and more or less mamillose; those of lower 
part of leaf, pale, smooth and elongate-hexagonal to rectangular. 
Perichaetial leaves usually not greatly differentiated. Seta erect, 
often strongly twisted. Capsule oblong to cylindric, erect or 
nodding and curved, with stomata mostly few, in the basal part, 
the columella often projecting above the rim; the lid conic to more 
- or less beaked. Annulus compound, often persistent. Peristome 
densely papillose, the sixteen teeth (sometimes scarcely devel- 
oped in D. obtusifolius) from a basilar membrane usually ex- 
tending well above the annulus, mostly divided to near the base 
into two or three slender, erect or oblique forks, or the forks some- 
times quite irregular and more or less united above. Calyptra 
cucullate, descending well below the lid. 
Type species: Dicranum latifolium Hedw. 
Capsule erect and symmetric or nearly so; leaf margin of one 
thickness of cells. 
Cells of upper part of leaf more or less densely papillose 
with variously shaped papillae. 
Leaf-margins somewhat recurved and leaves hair- 
pointed (except in D. latifolius muticus which 
is distinguished from D. obtusifolius by the 
leaves with margins partly flat and twice as 
long, 2.5—3 mm., and by the spores, 20 u in- 
stead of 8-10 uw); the older leaves without a 
distinct golden-brown border. 
Monoicous. 
/ Upper leaves with blade usually 2-3 mm. 
long. 
More or less spatulate or oblong, the 
upper marginal cells mostly obscure 
and rough with numerous papillae. 1. D. latifolius. 
Gradually tapering from below the mid- 
dle to an acute point. 2. D. suberectus. 
Upper leaves with blade 1.5 mm., or less, 
long, the upper marginal cells distinct 
with few or no papillae. 3. D. Guepint. 
Dioicous; blade of leaf about 2.5 mm. long. 4. D. plinthobius. 
Leaf-margins mostly strongly revolute all round and : 
leaves not hair pointed. 5. D. obtusifolius. 
Leaf-margins flat, the older leaves with a distinct, ; 
golden-brown border. 6. D. Portert. 
Cells of upper part of leaf never papillose, distinct, mostly 
mamillose on one or both sides. - 
Median leaf-cells 15-20 u and spores about 25 4 in 
diameter. 4. D. systilius. 
