Polyirichum.] iv. musci. 453

A large and remarkable geuas, of osaally rigid, brown or lurid'green mosses, often large,
sometimes gigantic ; found in both temperate and tropical climates, but far most abundantly
in the former, reaching the Arctic circle.
A. Calyptra nearly glabrous.
I. Atrichum, Palisot. Stem simple. Nerve of (toothed) leaf

narrow. Capsule terete ; operculum with a long beak . . 1. F. angustatum.
II. Oligoteichum, DC. Stem simple. Nerve of (entire) leaf

broad. Capsule ovoid or obloug ; operculum long . . . 2. P. tenuirostre.
III. PsiLOPiLUM, BrideL Stem simple. Nerve of leaf grooved

or lamellate. Capsule terete ; operculum small.
Leaves spreading, toothed. Teeth 32 3. P. crispulum.
Leaves suberect, quite entire. Teeth 16 4. P. australe,

IV. PoLTTRiCHADELPHUS, C. Muell, (OgpAoma, Hook. f. and

Wils.) Stem simple or dichotomous. Capsule horizontal,

flat above, concave below 5. P. Magellanicum.
v. Phalacroma, Hook. f. and Wils. Stem tall, fastigionsly
branched, dendroid. Capsule short, terete.
Stem 4-10 in. high. Leaves linear, from an ovate base . . 6. P. dendroides.
Stem 2-4 in. high, scaly. Leaves lanceolate-subulate . . . 7* P* squamosum.
B. Calypira clothed with matted hairs.
VI. PoooNATUH, Palisoi. Stem simple or branched above. Capsule

terete or nearly so. Apophysis 0.
Stem 1-2 in. Operculum shortly beaked 8, P. tortile.
Stem 2-4 in. Operculum with a long beak 9. P. alpinum.
VII. EuPOLTTRiCHUM, C. Muell. Stem simple or dichotomous.
Capsule angled, apophysate.
Capsnle 4-angular. Leaves quite entire ....... 10. P. juniperinum.
Capsnle 4-augular. Leaves serrate ; perichsetial distinct . .11. P. commune.
Capsule 4-6-angular. Leaves serrate ; perichffitial . . . 12. P. gradle.
