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C H A P T E R I V .
THE REPRODUCTIVE SYSTEM.
T he organs n e c e s sa ry for imp regnation and su b sequen t fruit formation
are o f tw o kinds, antherid ia— male, and a rch egon ia or
pistillidia— fem ale ; th e y differ, h ow e ve r, from th ose o f th e frondose
mosses, and are a rran ged in a different manner. T h e s e tw o organs
h a v e n e v e r been found to g e th e r in one inflorescence (synoicous),
as is so freq u en tly th e ca se in mosses, bu t th e y oc cur sep a ra te ly on
la te ra l sh oo ts e ith e r o f th e capitulum or o f some o f th e fascicles
b e low it, and th e y m a y b o th b e p rodu ced on one stem, or th e
different organs a re on sep a ra te p la n t s ; th us a ll Sphagna are e ith e r
monoicous or dioicous.
T he A n th e r id ia .
T h e se are arranged in slender catkins or amentula, somewhat
resembling those found in the Jungermanniacece, and occupy the
apical part o f a certain number o f the divergent branches, or by a
continued growth o f the branch beyond the male inflorescence, the
latter not unfrequently appears confined to the centre o f the
branch.
Ea ch antheridium is attached to the branch singly at the end
o f the insertion o f its covering bract, to which it stands in the
same relation as the branch fascicles do to the stem leaves.
T h e antheridium originates in a cell derived from the outer
indurated stratum o f the branch ; this cell divides b y a transverse
septum into two, the lower one becoming the slender pedicel, the
upper the globose body containing the antherozoids; the wall o f
the antheridium consists o f a single stratum o f large, angular, clear
cells. T h e pedicel is long and o f extreme tenuity, the sac globose
or ovate, and pale green, appearing as if encircled b y a hyaline
r in g ; this, however, is not the case, although Hedwig and some
recent bryologists have regarded it as such, and compared it to the
jointed annulus o f the Ferns, but the appearance is due to the large
cells being so transparent that they are only seen distinctly when
we view them in profile, and also to the central aggregation o f the
contents o f the organ. T h e antheridium bursts at the apex, the
margins o f the aperture rolling back, and a cloud o f lenticular
vesicles escapes, each o f which contains a spirally coiled an-
therozoid. T h e antherozoids are soon set free, and glide about
with great activity ; their form is that o f a fine thread o f 2\ coils,
clavately thickened at one end, and at the opposite attenuated
extremity provided with two long, extremely fine vibratile lashes.
Surrounding the antheridia are exceedingly fine web-like
paraphyses, which differ widely from those o f mosses in being
branched and twisted ; they arise from the cuticular layer o f the
branch, and no doubt convey moisture to sustain the vitality o f
the ■ antheridium, but they disappear as soon as fertilization of
the archegonium is completed.
T h e bracts or covering leaves of the male inflorescence resemble
the ordinary branch leaves in structure, but are shorter and more
closely imbricated, and also often richly coloured, being purple in
S', acutifolium, fulvous in S', cymbifolium, ochraceous in S', intermedium,
&c.
T he A rchegonium.
T h e female inflorescence appears on a short lateral branch at
the side o f the capitulum, and at first takes the form o f a long,
attenuated, deep green bud o f sheathing perigynial leaves, the
innermost of which are the longest. Within these, and surrounded
by the rudimentary perichætial bracts, are one to four archegonia,
resembling those of true mosses, but having fine branched paraphyses
like those o f the male inflorescence. T h e y have shorter
pedicels, and consist o f an oblong ventral part which elongates
upward into a cylindric neck or stylidium, formed b f six rows of
cells.
T h e first formation of the archegonia and progress o f their
development are fully described in the respective treatises of
Hofmeister and Schimper. When arrived at maturity the apex o f
the archegone swells up and bursts, and the margins rolFback,
leaving a trumpet-shaped orifice ; this aperture extends downward
as a fine tube to the cavity o f the archegonium, and forms
the channel down which the antherozoids pass to fertilize the
central cell.
M. Roze observed the mode o f impregnation o f the archegone
by placing some mature but still closed ones in water on a slide.