124. H o m a lo t h e c iu m . Teeth closely articulate, liyalme-hordered,
sef'iiieiits free, short, linear-lanceolate, or longer and adhering to
the teeth. Calyptra hairy. Capsule slightly cernuous or erect.
127. O r t h o th e o iu m . Capsule erect or subinclined. Teeth hyaline
on the margin; segments linear, as long as the teeth; ciiia short
or none. Leaves not costate.
= = Inner peristome divided nearly to the middle into 1C segments;
cilia 2 or 3.
128 H v p n u m . Capsule cernuous, arcuate or horizontal, rarely erect.
Feiistome perfect; cilia articulate or appendiculate.
* * Calyptra mitriform. Capsule exserted, horizontally inclined.
112. H o o k e r ia . Teeth lanceolate; segments linear-lanceolate; cilia
none. Leaves bicostate. Plants small.
113 P t e r ig o p h y l lu n i . Peristome as in the last. Plants large.
Leaves large, entire, ecostate; areolation very loose.
MA NUA L
NORTH AMERICAN MOSSES.
Oed ek I. SPHAGNACEH5. P e a t M o s se s .
Soft and flaccid caulescent Mosses, generally of large size,
growing in more or less compact tufts or patches on the surface
of bogs, or floating in stagnant water, more rarely on the borders
of mountain rivulets, whitish, yellowish, sometimes red
or olive-colored, perennial by the annual prolongation of the
stems or by simple innovations at the apex. Stems mostly undivided
and bearing copious lateral branches, composed of a
triple cellular tissue, the outer (cortex) of large loose cells, the
intermediate woody, the central parenchymatöse or medullary.
Branches partly spreading, partly deflexed and appressed to the
stem, in lateral fascicles of 2 to 7, rarely more, those at the
summit of the stem capitate, the fascicles gradually more distant
downward. Leaves nerveless, translucent, formed of a
single layer of two kinds of cells; 1st, large colorless, and hyaline
ones (utricles), generally perforated by pores and lined
with spiral or circular filaments (fibrils), hence fibrillose and
porose ; 2d, smaller chlorophyllose ones (ducts), narrowly linear,
continuous, forming a net of rhomhoidal or hexagonal meshes
around the utricles: stem-leaves distant, obliquely inserted,
erect or dcflexed, flat or concave, ovate, obovate, or linguiform,
generally obtuse, loosely areolate, their utricles often destitute
of fibrils and of pores; branch-leaves smaller, imbricated and