13. R h y n c h o s t e g ium . Stems more or less compressed. Leaves
nearly entire, simply costate, rarely shortly hicostate; areolation
rhomboidal, somewhat loose, enlarged at base.
14. T h am n ium . Plants large, dendroid; stem woody. Stem-leaves
scarious; branch-leaves strongly dentate; cells minute, round-
oval, the basilar longer. Capsules clustered.
C. Plants variously divided. Capsules cernuous, rarely suberect; operculum
conic or rostrate.
* Leaves thin, glossy, open, erect or spreading.
15. Plagiothecium. Branches few, mostly simple, complánate.
Leaves slightly unsymmetrical at base; costa none, or double
and very short; areolation rhomboidal-elongated, little enlarged
at base. Capsule suberect; operculum conic or rostrate.
16. A m b ly s t e g ium . Stem creeping and widely spreading. Leaves
mostly entire, opaque or glossy; costa simple, rarely none; areolation
^ distinct, rhomboidal. Capsule cylindrical-oblong; lid
17. Campylium. Stem irregularly divided with pinnate or fastigiate
branches. Leaves spreading, subsquarrose; costa short or none;
areolation minute, flexuous.
* * Leaves falcate-secund, of solid membranous texture,
18. Harpidium. Stems pinnately ramulose. Leaves simply costate
to the apex; areolation very narrow, linear, much inflated at the
concave basilar angles.
19. Cratoneurum. Stems prostrate; branches erect, rigid, villous,
pinnate. Leaves simply and strongly costate; areolation dense,
linear, oblong at the enlarged base and decurrent angles. Capsule
cylindrical, cernuous.
20. Rhytidium. Stems large, prostrate, irregularly pinnate with short
subnncinate branchlets. Leaves secund and subfalcate, undulate
rugose; areolation compact, linear. Capsule cylindrical
arcuate.
21. Ctenium. Branches in compact tufts, pinnately ramulose. Leaves
hamate and circinnate-secund. Capsule cylindrical.
22. Ctenidium. Plants cespitóse; branches erect, appressed, regularly
pinnately ramulose. Leaves soft, circinnate-secund. Capsule
short, cernuous, solid.
23. Hypnum, proper. Plants variously divided; branches more or less
densely pinnately ramulose. Leaves obscurely bicostate, membranous,
shining; areolation compact, narrowly rhomboidal,
distinctly quadrate at the angles. Capsule oblong, erect-cer-
nuous.
* * * Leaves more or less closely imbricate, round or oblong, obtuse or
pointed, deeply concave.
24. Limnobium. Plants prostrate, irregularly branching. Leaves
slightly unequal at the clasping and decurrent base, simply costate
or obscurely bicostate. Capsule short, turgid-ovate, cernuous.
25. Callierg-on. Stem erect, with few terete turgid branches. Leaves
very concave, membranous; areolation very compact, narrow,
enlarged-quadrate at the angles. Capsule oblong, horizontally
cmwed.
* * * * Plants veiy large. Leaves turgid, rugulose.
26. S c o r p id iu m . Stems irregularly divided. Leaves large, lanceolate
acuminate or broadly oblong and acute or obtuse ; areolation
very close and narrow ; basal cells numerous, quadrate. Capsule
cylindrical, arched.
D. Plants large ; divisions arcuate, ascending or proliferous ; iraraphyllia
numerous.
27. P l e u r o z iu m . Stem arcuate, prostrate and proliferous; branches
bi-tripimiate. Leaves membranous, shining, shortly hicostate or
semicostate ; areolation linear, narrow, uniform. Capsule round-
ovate.
28. H y lo o o m iu m . Stems with few branches, pinnately fastigiateramulose.
Leaves squarrose or reflexed, shortly bicostate ; areolation
linear, narrow, somewhat enlarged at base. Capsule short,
turgid, horizontal.
S u bg en u s I. PSEUDOLESKEA. (PL 6.)
Mode of growth and arrangement of the leaves and paraphyllia
as in Leskea. Capsule cernuous or horizontal, short,
turgid, thick-walled. Teeth of the peristome solid ; membrane
large ; segments as long as the teeth, regular, carinate, cleft
between the articulations, generally separated by more or less
perfect cilia. — Pseudoleskea, Bruch & Schimp.
1. H. a tro v ire n s , Dicks. Densely cespitose, dark green;
stem much divided and suhpinnately ramulose ; branchlets
flexuous : leaves minutely papillose, open or subsecund, lanceolate
from an ovate base, concave, entire, the borders recurved ;
costa stout, vanishing below the apex; paraphyllia numerous
and multiform : capsule cernuous or horizontal, oval or oblong,
more or less turgid, dark brown, constricted under the orifice
when dry and empty ; pedicel smooth, curved above ; oporeulnm
convex-conical, acute or apiculate ; cilia none ; annulus very
narrow, simple. — Crypt. Fasc. ii. 10 ; Smith, Engl. Bot. t. 2422.
II. filamentosum, Dicks. 1. c. Pseudoleskea ati-ovirens, Bruch
& Schimp. Bryol. Eur. t. 477.
IIab. On rocks; Niagara Falls and Lake Superior (Macoun); Lake
Huron (Mrs. Boy); very rare, and sterile.
2. H. c a te n u la tum , Brid. Mode of growth as in the last ;
leaves very small, spreading when moist, closely imbricate when
dry, lanceolate from an ovate base ; borders recurved from the
middle downward; costa flat, vanishing in the middle; cells
small, oval, uniformly oblique at base; paraphyllia filiform.