Fig. 349. Peatmosses. A, tip of female branch of S. acutifolium, cut vertically to show the archegonia (ar), protective leaves (ch) still young, and older ones (y) acting like bud scales. B, young fruit, cut vertically to show the sporophyte of which the foot (sg') is fixed in the head (v) of the stalk or pseudopodium (ps), and the spore case (sg) is still enveloped by the calyptra (c) bearing above the old neck (ar) of the archegonium. C, ripe sporophvte of S. squarrosum, showing its lid (d) and spore case (sg) emerged from the torn calyptra (c) and borne upon a pseudopodium pushing it beyond the formerly protecting pseudo leaves (ch). All magnified.

Fig. 349.-Peatmosses. A, tip of female branch of S. acutifolium, cut vertically to show the archegonia (ar), protective leaves (ch) still young, and older ones (y) acting like bud-scales. B, young "fruit," cut vertically to show the sporophyte of which the foot (sg') is fixed in the head (v) of the stalk or pseudopodium (ps), and the spore-case (sg) is still enveloped by the calyptra (c) bearing above the old neck (ar) of the archegonium. C, ripe sporophvte of S. squarrosum, showing its lid (d) and spore-case (sg) emerged from the torn calyptra (c) and borne upon a pseudopodium pushing it beyond the formerly protecting pseudo-leaves (ch). All magnified. (Schimper.)

In Funaria (Figs. 350-356) the spores when germinating (Fig. 350) produce a much-branched thread which makes a bright green, feltlike layer on moist earth. From this thread at many places arise directly vertical pseudo-shoots each consisting of an axis bearing delicate pseudo-roots from the lower part, pseudo-leaves arranged spirally along the sides, and at the tip either male or female gametangia (Figs. 351-353). The gametophyte in Funaria is thus of somewhat simpler constitution than in Sphagnum. The cellular structure also shows less differentiation. On the other hand, the sporophyte is more complex. As shown in Figs. 354, 355 the foot becomes a long stalk, and the capsule develops several different tissues. The calyptra ruptures transversely at the base and is carried up on the capsule as a hood which falls off after the capsule is mature. A cylindrical spore-layer surrounds an inner mass of cells and certain inner cells of the lid break so as to leave behind on the capsule after dehiscence a fringe of teeth, called the peristome.1 Its function is to protect the spores and keep them from being blown out by a light breeze which would carry them only a short distance.

1 Per'i-stome - Gr. peri, around; stoma, mouth.

Fig. 350. Cord moss (Funaria hygrometrica, Cord moss Family, Funariaceoe). A, germinating spore (440/1) showing a sap filled cavity or vacuole (v) a pseudo root (w, w), and the old outer spore wall (s). B, further development of the thread (protonema) which comes from the spore, showing the main thread (h) and side branches from one of which (b) is growing a bud (K) destined to form a pseudo stem and pseudo leaves, and already sending out a pseudo root (w), 72/1.

Fig. 350.-Cord-moss (Funaria hygrometrica, Cord-moss Family, Funariaceoe). A, germinating spore (440/1) showing a sap-filled cavity or vacuole (v) a pseudo-root (w, w), and the old outer spore-wall (s). B, further development of the thread (protonema) which comes from the spore, showing the main thread (h) and side branches from one of which (b) is growing a bud (K) destined to form a pseudo-stem and pseudo-leaves, and already sending out a pseudo-root (w), 72/1. (Sachs.)

Fig. 351. Cord moss. Tip of a male gametophyte cut vertically to show the male gametangia (antheridia) of various ages from young (a) to almost full grown (b); also paraphyse (c), protective pseudo leaves (d) and foliage pseudo leaves (e), 200/1.

Fig. 351.-Cord-moss. Tip of a male gametophyte cut vertically to show the male gametangia (antheridia) of various ages from young (a) to almost full-grown (b); also paraphyse (c), protective pseudo-leaves (d) and foliage pseudo-leaves (e), 200/1. (Sachs.)

Fig. 352. Cord moss. A, antheridium discharging its spermatozoids (a), 350/1. B, b, spermatozoid not yet escaped from its cell wall; c, the same swimming freely.

Fig. 352.-Cord-moss. A, antheridium discharging its spermatozoids (a), 350/1. B, b, spermatozoid not yet escaped from its cell-wall; c, the same swimming freely. (Sachs.)

Fig. 353. Cord moss. A, tip of a female gametophyte cut vertically to show the female gametangia (archegonia) surrounded by pseudo leaves (b), 80/1. B, an archegonium showing the swollen lower part (b) containing an unfertilized egg cell, the neck (h) with its orifice (m) still closed and the axial row of cells being converted into mucilage, 400/1. C, orifice of an archegonium after fertilization, with its cell walls colored dark red, 500/1.

Fig. 353.-Cord-moss. A, tip of a female gametophyte cut vertically to show the female gametangia (archegonia) surrounded by pseudo-leaves (b), 80/1. B, an archegonium showing the swollen lower part (b) containing an unfertilized egg-cell, the neck (h) with its orifice (m) still closed and the axial row of cells being converted into mucilage, 400/1. C, orifice of an archegonium after fertilization, with its cell-walls colored dark red, 500/1. (Sachs.)

Fig. 354. Cord moss. A, embryo of sporophyte (f, f') still within the archegonium (b, b), cut vertically, h, being the neck, 375/1. B, C, more advanced stages in the development of the sporophyte (f) covered by the old archegonium or calyptra (c) upon which the neck (h) still remains, 30/1.

Fig. 354.-Cord-moss. A, embryo of sporophyte (f, f') still within the archegonium (b, b), cut vertically, h, being the neck, 375/1. B, C, more advanced stages in the development of the sporophyte (f) covered by the old archegonium or calyptra (c) upon which the neck (h) still remains, 30/1. (Sachs.)

Fig. 355. Cord moss. A, female gametophyte bearing pseudo leaves (g) and a calyptra (c) still protecting a young sporophyte, 1/1. B, same, at a later stage when the calyptra (c) has been carried up as a hood on top of the spore case (f) by the elongation of the stalk (s) of the sporophyte, 1/1. C, spore case or capsule, enlarged and cut vertically to show the lid (d), a connecting row of cells, the annulus (a), a row of projections, the peristome (p) covering the mouth, a central mass of cells, the columella (c, c), air spaces (h), and the layer of spores (s), 8/1.

Fig. 355.-Cord-moss. A, female gametophyte bearing pseudo-leaves (g) and a calyptra (c) still protecting a young sporophyte, 1/1. B, same, at a later stage when the calyptra (c) has been carried up as a hood on top of the spore-case (f) by the elongation of the stalk (s) of the sporophyte, 1/1. C, spore-case or capsule, enlarged and cut vertically to show the lid (d), a connecting row of cells, the annulus (a), a row of projections, the peristome (p) covering the mouth, a central mass of cells, the columella (c, c), air spaces (h), and the layer of spores (s), 8/1. (Sachs.)

Fig. 356. Cord moss. A, spore case, showing peristome and twisted stalk. B, cells of the annulus. C, breathing pores (stomata). D, teeth of the peristome. E, spore case cut vertically, F, young spore case still covered by the calyptra. Variously magnified. (Baillon.) Common on waste or barren soil.

Fig. 356.-Cord-moss. A, spore-case, showing peristome and twisted stalk. B, cells of the annulus. C, breathing-pores (stomata). D, teeth of the peristome. E, spore-case cut vertically, F, young spore-case still covered by the calyptra. Variously magnified. (Baillon.)-Common on waste or barren soil.

In dry weather, after calyptra and lid have fallen, a strong wind will shake the capsule on its slender elastic foot-stalk, and scatter the spores out between the teeth. The most remarkable difference between the sporophytes of Funaria and Sphagnum is that the former like that of Anthoceros contains chlorophyll and is thus able to manufacture a large part of its own food while the latter is like the sporophytes of Riccia and Marchantia in being entirely parasitic upon the gametophyte. Inorganic materials absorbed by the slender pseudo-roots of the gametophyte are supplied to the foot of the stalk and thence conducted to the photosynthetic tissue of the capsule. Conduction take places mainly through a central cylinder which consists of cells elongated in the direction of the axis and with pointed ends which interlock. Such a tissue is termed prosenchyma 2 in contrast with parenchyma 3 which is composed of cells not much elongated, and without pointed ends, as is the case with nearly all the tissues we have so far studied. At the surface of the sporophyte is a protective layer of cells, distinguished as the epidermis;4 the looser, mostly green tissue which lies between the epidermis and the central cylinder being termed the cortex.5 In the epidermis near the base of the capsule occur peculiar openings called stomata 6 communicating with the internal air-spaces of the cortex. Each opening is guarded by two special cells which might be likened to lips. It is by means of these breathing pores that the interior tissues are aërated. Whereas in the sporophyte of Sphagnum we have a very simple sporangium from which there is differentiated a small foot and the merest hint of a short connecting stem; in Funaria we find a long slender stalk, homologous with the foot, bearing a capsule made up of the sporangium partly inclosed by an urn-like mass of tissue which we may call the shoot. Funaria represents about as high development of the sporophyte as moss plants have ever attained.

2 Pros-en'chy-ma - Gr. pros, before; en, in; cheo, pour.

3 Par-en'chy-ma - Gr. para, beside. A term applied by the earlier anatomists to the main tissue of such organs as the lungs which they supposed was formed of material poured in beside the vessels and nerves that had been " poured in " before.

4 Ep-i-der'mis - Gr. epi, upon, i. e., outer; derma, skin.

5 Cor'tex - L. cortex, rind or bark.

6 Sto'ma - Gr. stoma, a mouth.