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Transactions of the Society . 
female are on different plants, autoicous when both are on the same 
plant, synoicous when both kinds of sexual organs are combined in 
one inflorescence, paroicous when the antheridia are in the axils of 
bracts below the archegonia. The floral leaves which enclose the 
sexual organs are called bracts, and are smaller and thinner than the 
ordinary leaves; the antheridia are clavate or sausage-shaped with a 
short pedicel, and are generally accompanied by paraphyses, their walls 
consist of a single stratum of cells, and their contents are the mother- 
cells of the antherozoids. The ^emmiform male inflorescence is the 
most frequent, and stands in a leaf-axil or in the fork of two branches 
in the form of a little closed bud, the perigonial bracts overlapping 
each other, and drawn together at the apex. Capitate male inflor- 
escence is terminal, somewhat spherical, with an open centre and 
bracts recurved at apex, as in Splachnum. Discoid inflorescence is 
also terminal, the bracts expanded and larger, and in Polytrichum 
very noticeable by their crimson or orange colour, as also by a new 
shoot often perforating the disc and also ending in a terminal male 
inflorescence, which may be repeated in several successive seasons. 
The archegonia or pistillidia are flask-like with a thick foot, ventricose 
body, and style-like neck ; the wall of the body consists of 1-4 layers 
of cells. 
The Capsule. — The impregnated oospore rapidly enlarges the 
ventral part of the archegone, and the young sporogone, enveloped in 
its calyptra, becomes elevated on the seta, which is often of considerable 
length, generally red or brown, and imbedded by its foot in the tissue 
of the stem beneath it ; its outer cells are strongly thickened, so that 
it is frequently of wiry texture, and its surface is often rough with 
small nodules ; in drying it becomes flattened and thus twists on its 
axis, usually the upper and lower parts turning in different directions, 
the upper part to the left, the lower to the right. 
The vaginula encloses the foot and base of the seta, and is often 
covered with abortive archegonia and paraphyses, and in Orthotrichum 
and a few other genera bears at its apex a short and delicate funnel- 
shaped tube — the ochrea. 
The calyptra invests the capsule in its young state, and consists 
of one or more strata of cutioular cells, the apex being the withered 
neck of the archegonium. As soon as it is torn from the vaginula, 
the seta carries it up on its apex, enclosing and protecting the young 
capsule, and its form is important for systematic purposes. It takes 
two principal forms : (1) dimidiate or cucullate, when slit up on one 
side and sitting obliquely on the capsule, as in Dicranum and Tor- 
tula ; (2) mitraeform, when regular and erect, the mouth being 
sometimes fringed or lobed, and the surface being smooth or plicate, 
papillose or hairy, as in Orthotrichum. In Sphagnum and Archidium 
the calyptra is large and saccate and tears irregularly. 
The capsule, theca, or sporangium is regular when it is sym- 
metric, or irregular when unsymmetric ; its form is variable, being 
