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Here is a list of twenty Bryophytes:- 1. Riccia 2. Marchantia 3. Conocephalum 4. Lunularia 5. Dumortiera 6. Targionia 7. Fimbriaria 8. Reboulia 9. Plagiochasma 10. Pellia 11. Porella 12. Metzgeria 13. Anthoceros 14. Notothylas 15. Sphagnum 16. Pogonatum 17. Taxithelium 18. Funaria 19. Bryum 20. Fissidens.
1. Riccia:
Vegetative Structure:
Plant body is thallose, dorsiventrally differentiated, prostate with dichotomous branching. Each dichotomy is linear to wedge-shaped and the median portion is thickened. There is a conspicuous longitudinal furrow on the dorsal side.
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The ventral surface bears a corresponding ridge and a transverse row of scales, one cell in thickness, which are more crowded near the apex and overlap the growing point. Lower down, the scales are in two marginal rows, violet in colour. In addition, there are two types of rhizoids – smooth walled and tuberculate, being on the ventral ridge of the thallus.
In T.S. through the thallus, the following layers can be seen:
(a) Dorsal side bears a tissue in which there are a few vertical rows of chlorophyllose cells separated by narrow vertical air canals, so that the top of the thallus is porose. This is chlorophyllose or assimilatory tissue.
(b) Ventral region of the thallus is formed by a compact colourless parenchymatous tissue which serves as the storage region and often contains starch. One cell thick scales and unicellular rhizoids (smooth walled and tuberculate) are developed from the outermost layer of the ventral surface. Upper epidermis is one layered with colourless cells. Air pores are bounded by four epidermal cells as seen in tangential section. Lower epidermis is a continuous layer.
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Reproductive Structure:
Plants are mostly monoecious but rarely dioceious. Sex organs develop singly and acropetally in a linear row on the dorsal median furrow. The mature antheridium is stalked, pear-shaped and its single layered jacket (wall) encloses a number of sperm or androcyte mother cells.
Mature archegonium is flask-shaped with a short stalk, a swollen basal venter containing the large egg together with a ventral canal cell and an elongated neck containing a row of four neck canal cells. Sex organs are embedded within the thallus and included in air chambers (antheridial and archegonial chambers).
Sporogonium is somewhat round, sac-like and embedded within the thallus. It contains a single layered jacket (gametophytic cells) enclosing many spores which are often in tetrads. Mature spores show 3 layers exosporium (outermost), mesosporium (middle) and endosporium (innermost). Spores often remain in tetrads (Fig 5.1).
Identification:
Thallus dorsiventrally flattened and prostrate; sporophytes simple and always of limited growth, columella absent inside capsule.
CLASS: HEPATICOPSIDA
Plant body prostrate, ribbon-shaped, dichotomously branched, dorsiventrally flattened; dorsal tissue layers green and with air canals or chambers; thallus with scales and rhizoids on ventral surface, sex organs on dorsal surface (embedded), sporophyte devoid of columella or elaterophore.
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ORDER: MARCHANTIALES
Sporophyte having only sac-like capsule and embedded within the gametophytic thallus; thallus dichotomously branched with sex organs along the entire length of the median furrow.
FAMILY: RICCIACEAE
Thallus linear to wedge-shaped internally composed of vertical rows of cells on the dorsal side, air canal present in between two vertical rows of cells; sporophyte sac-like and having one-layered jacket surrounding spores and nurse cells.
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GENUS: RICCIA
2. Marchantia:
Vegetative Structure:
Plant body is thallose, dichotomously branched, dorsiventrally differentiated and prostrate. Dorsal surface of the thallus shows regular rhomboidal or polygonal areas with elevated pores at the centre of these areas.
There is a prominent midrib on the dorsal surface of the branches and corresponding ridge on the ventral surface. Ventral surface bears 3-4 rows of scales on each side of the ridge. In addition, there are two types of rhizoids in between the scales – smooth-walled and tuberculate.
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In T.S. through thallus, the following layers of tissues can be noticed:
(a) The uppermost dorsal layer of cells i.e. upper epidermis is formed by quadrate cells.
(b) There are sub-epidermal air chambers with elevated air pores – at the centre of each chamber.
(c) There is presence of branched and un-branched photosynthetic filaments in air chambers (chlorophyllose or assimilatory tissue).
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(d) Ventral part of the thallus possesses compact, colourless, parenchymatous cells (storage tissue).
(e) On the ventral surface scales and rhizoids is present arising from lower epidermis. In tangential section, air pores are seen as barrel-shaped structures formed by 4 – 8 superimposed tiers of concentric rings, each ring being composed of 4 – 5 cells. Four inward projections arising from the lowermost tier give it a star-shaped appearance (cruciate air pores).
Reproductive Structure:
Gemma cups are present on the dorsal surface of thallus along the midrib. Gemma cup possesses a large number of stalked gemmae. Gemmae are multi cellular stalked discoid bodies with constriction in the middle.
Plants are dioecious. The sex organs are borne on special branches (receptacles) called antheridiophore and archegoniophore. The antheridiophore shows a prismatic stalk bearing at its apex a disc which is usually 8-lobed; each lobe bears antheridia along a dorsal median row. Each antheridium is short-stalked and developed within the thallus in an antheridial chamber.
Mature antheridia show a single-layered jacket enclosing sperm mother cells. The archegoniophore or the carpocephalum also has a stalk and a disc. This disc bears 9 rays. Each ray has a row of archegonia hanging downward. A mature archegonium shows a swollen venter with an egg together with a ventral canal cell and neck canal cells in the neck region (Fig 5.2 & 5.3).
Sporogonium:
Sporophyte is differentiated into foot, seta and capsule and protected by calyptra, perichaetium and perigynium. Mature capsule is elliptical and has a single-layered jacket and contains spores and elaters. Spores are very small and somewhat rounded. (Fig 5.3).
Identification:
Thallus dorsiventrally flattened and prostrate, sporophyte simple and with limited growth columella absent inside the capsule.
CLASS: HEPATICOPSIDA
ADVERTISEMENTS:
Plant body prostrate, ribbon-shaped, dichotomously branched, presence of dorsal chamber, sex organs on dorsal surface, sporophyte devoid of columella or elaterophore.
ORDER: MARCHANTIALES
Antheridia and archegonia localised on special branches-antheridiophore and archegoniaphore. Sporophyte differentiated into foot, seta and capsule, elaters present.
FAMILY: MARCHANTIACEAE
Air chambers present in a row, pores elevated, photosynthetic filaments present, presence of antheridiophore and archegoniophore, sporophyte with foot, seta and capsule. Capsule bears spores and elaters.
GENUS: MARCHANTIA
3. Conocephalum:
Vegetative Structure:
Plant body is thalloid in nature and the thallus is large, dichotomously branched and dorsiventrally differentiated. Dorsal surface of the thallus is areolate, and areolae are very distinct and mostly hexagonal. Dorsal surface of the thallus is dark green, but ventral surface is pale green. Midrib is very conspicuous. There are a few scales arranged in two rows on ventral surface by the side of midrib, along with unicellular, smooth-walled and tuberculate rhizoids.
In T.S. through the thallus the following layers can be noticed:
(a) Single-layered upper epidermis with simple, elevated airpores, visible to the naked eye.
(b) Presence of dorsal layer with large air-chambers, where filamentous, chlorophyllous cells arising from the floor are produced into pointed beaks.
(c) Parenchymatous storage tissue and lower epidermis with scales and 2 types of rhizoids are present.
Reproductive Structure:
Plants are dioecious. Male receptacle is disciform, papillose, sessile and situated near the apex of a branch, or sometimes apparently lateral in a cup formed by the growth of the thallus laterally and posteriorly. Female receptacle is nearly terminal, long-stalked and located in a pit. It is obtusely conical, almost entire and composed of 5-8 tubular involucres on the underside, each enclosing a single capsule. Parianth is absent.
Sporogonium:
It is composed of foot, seta and capsule. Capsule has a rather long pedicel and it is clavate-pyriform in shape. It dehisces at maturity by throwing off an apical cap, and the remaining part of jacket splitting longitudinally by 4 to 8 reflexed valves. Spores are large, papillose and many-celled. Elaters contain 2-4 spiral and bluntly fusiform thickening bands. (Fig 5.4).
Identification:
Thallus dorsiventrally flattened and prostrate sporophytic simple and with limited growth, columella absent.
CLASS: HEPATICOPSIDA
Plant body prostrate, sex organs on dorsal surface, sporophyte devoid of columella or elaterophores.
ORDER: MARCHANTIALES
Antheridia and archagonia localised on special branches, sporophyte differentiated into foot, seta and capsule.
FAMILY: MARCHANTIACEAE
Plants with air chambers and pores, capsule in involucres, female receptacle nearly terminal and stalked, dorsal surface of the thallus with distinct reticulations and pores.
GENUS: CONOCEPHALUM
4. Lunularia:
Vegetative Structure:
Thallus is large and irregularly furcate or innovating at the apex. Dorsal surface is distinctly areolar and also provided with simple pores and semilunar gemmae-cups.
In T.S., the thallus shows the following layers:
(a) Upper epidermal layer with pores, epidermal cells are 5 – 6 angled. Pores are raised and bounded by 3 rings of 6 – 8 cells each.
(b) Dorsal cortical chambers containing short, branched filamentous chlorophyllose cells.
(c) Parenchymatous cortical zone.
(d) Ventral epidermal layer with scales in one row on each side of midrib. Scales are thin delicate and attached by a long semilunar base.
(e) Rhizoids unicellular and smooth-walled and tuberculate.
Reproductive Structure:
Plants are dioecious.
Gemmae Cup:
It is semilunar, and the wall is very high posteriorly but gradually becoming lower forwards. Gemmae develop on unicellular stalks and are circular, biconvex in shape with two lateral notches. (Fig 5.5).
Male receptacle:
It is disciform, sessile and situated at the apex of a short branch, but becoming lateral with the development of female receptacle.
Female receptacle:
It is stalked, disciform and composed of 4 cruciate, horizontal, tubular involucres (each containing a single sporogonium).
Sporogonium:
It is composed of foot, seta and capsule. Capsule is dark brownish, and oval in shape. It is situated within an involucre. Spores are rounded, tetrahedral, smooth and yellowish brown. Elaters are long, slender, yellowish brown and bi-spiral
Identification:
Thallus dorsiventrally flattened and prostrate, sporophyte simple and with limited growth, columella absent.
CLASS: HEPATICOPSIDA
Plant body prostrate, sex organs on dorsal surface, sporophyte devoid of columella or elaterophores.
ORDER: MARCHANTIALES
Antheridia and archegonia localised as specialised clusters, sporophyte differentiated into foot, seta and capsule.
FAMILY: MARCHANTIACEAE
Plants with air chambers and pores on the dorsal surface, capsule in involucre, plant with gemmae cups on its dorsal surface. Gemmae cups semi-lunate in shape.
GENUS: LUNULARIA
5. Dumortiera:
Vegetative Structure:
Plants are very large, thallus greenish, prostrate, dichotomously branched, dorsiventrally differentiated, overlapping and usually grow as large expanded patches. Thallus shows repeated branching by apical innovations, apex notched and margin undulated. There is a prominent midrib on the thallus.
There are a few hyaline scales, occurring as narrow long oblique ridges attached to the ventral surface of the thallus on each side of the midrib and also smooth-walled and tuberculate rhizoids. The dorsal surface of the thallus is often covered with papillate cells and thereby giving it a velvety appearance.
In T.S. of the thallus the following layers can be noticed:
(a) Single-layered upper epidermis composed of 4 – 6 angled thin-walled cells
(b) Single layered lower epidermis with hyaline scales and rhizoids
(c) In between the epidermal layers there are chlorophyllose cells (Fig 5.6).
Reproductive Structure:
Plants are mostly monoecious. Male receptacles are terminally situated and often possess bristles on the margin. Each receptacle is disciform, depressed in the centre and sub-sessile. Female receptacles are sessile, when young, but stalked when mature. The female receptacles are also disciform, convex, umbonate and with a few bristle-like hairs.
Sporophyte:
There are 3 distinct zones – foot, seta and capsule. Capsule is globose, reddish-brown in colour and enclosed in involucres. It contains many tetrahedral spores, and the spore surface is densely and finely muricate and about 22 – 26 µm in diameter. Elaters are long, with 2-4 spiral thickening bands. Seta is long and foot is situated within the thallus.
Identification:
Thallus dorsiventrally flattened and prostrate sporophyte simple and with limited growth, columella absent.
CLASS: HEPATICOPSIDA
Plant body prostrate, sex organs on dorsal surface, sporophyte devoid of columella or elaterophore.
ORDER: MARCHANTIALES
Antheridia and archegonia localised as specialised clusters, sporophyte differentiated into foot, seta and capsule.
FAMILY: MARCHANTIACEAE
Capsule enclosed in involucres, not embedded in thallus. Thallus devoid of chambers or pores.
GENUS: DUMORTIERA
6. Targionia:
Vegetative Structure:
Thallus is simple and has ventral innovations near the apex or rarely dichotomously divided with indistinct areolae on the dorsal surface. Ventral surface with scales in two rows. Midrib prominent below and rather suddenly passing into the lamina. Rhizoids are unicellular, smooth-walled and tuberculate.
In T.S. through the thallus the following layers can be noticed:
(a) Upper epidermal layer with simple pores, epidermal cells are 5 – 6 angled.
(b) Dorsal air chambers with green filamentous zones. The filaments of the air chambers anastomosing and reaching the roof, except under the pore. Terminal cells of the filaments situated under the pores are hyaline, but in other places cells containing many chloroplasts. Each chamber is opened to exterior by slightly elevated pores.
(c) Parenchymatous zone.
(d) Lower epidermal layer with rhizoids and scales which are obliquely broad- triangular. Ventral surface is somewhat purple in colour (Fig 5.7).
Reproductive Structure:
Plants are monoecious or dioecious. Antheridia are aggregated on the discs of the short ventral shoots or on the dorsal side of the main shoot forming a long and broad mid-dorsal cushion. Archegonia are several and develop within involucres on the under-surface of the thallus towards the apex at early stage. Involucres are bivalved, subglobose, keeled, purple and each containing 5-6 archegonia in the early stage of development, but ultimately only one or two are transformed into sporogonia.
Sporogonium:
Capsule is spherical and has a short pedicel and well-developed foot. Capsule wall is one-layered with spiral and annular bands. Spore wall is reticulate and elaters are long and bi-spiral.
Identification:
Thallus dorsiventrally flattened and prostrate, sporophyte simple and with limited growth, columella absent.
CLASS: HEPATICOPSIDA
Plant body prostrate, sex organs on dorsal surface, sporophyte devoid of columella or elaterophores.
ORDER: MARCHANTIALES
Sporophyte differentiated into foot seta and capsule.
FAMILY: MARCHANTIACEAE
Plants with air-chambers and pores, ventral surface with scales, capsule in involucre, plants without gemmae cups. Archegonia in a tubular bivalved involucre just under the apex, involucre purple.
GENUS: TARGIONIA
7. Fimbriaria:
Vegetative Structure:
Plants are thalloid and innovating from the apex. Ventral surface possesses scales with appendages in rows on each side of the midrib. Thallus is dichotomously branched, dorsiventrally differentiated, apex notched and with entire margin. Fresh thallus has characteristic fishy smell. Rhizoids are unicellular, smooth-walled and tuberculate.
In T.S. through thallus, the following layers can be seen:
(a) Dorsal epidermal layer with polyhedral cells, and having pores bounded by two series of 6 cells each;
(b) Dorsal air chambers with photosynthetic filaments;
(c) Parenchymatous layers and ventral epidermal layer with scales and rhizoids (Fig 5.8).
Reproductive Structure:
Plants are monoecious or dioecious. Male receptacle is sessile, naked, disc-shaped or cushion-like and situated just behind the stalk of the female receptacle. Female receptacle is terminal and situated on the main shoot or on small ventral shoots. It is stalked, convex and 4-lobed. Archegonia are surrounded by involucres, which are cup-shaped or campanulate.
Sporogonium:
One in each involucre. Each sporogonium has foot, seta and capsule. Capsule is globose, shortly pedicelled, capsule wall is single-layered. Spores are tetrahedral, reticulate – lamellate on the convex side. Elaters are short, simple or furcate, mono or bi-spiral.
Identification:
Thallus dorsiventrally flattened and prostrate, sporophyte simple and with limited growth, columella absent.
CLASS: HEPATICOPSIDA
Plant body prostrate, sex organs on dorsal surface, sporophyte devoid of columella or elaterophores.
ORDER: MARCHANTIALES
Sex organs develop in a cluster on a specialised stalk, sporophyte differentiated into foot, seta and capsule.
FAMILY: MARCHANTIACEAE
Plants with air-chambers and pores, ventral surface with scales, capsule in involucres, Gemmae cup absent, male, receptacle sessile, archegonia stalked, terminal with a characteristic perianth. Fresh plants have a characteristic fishy smell.
GENUS: FIMBRIARIA
8. Reboulia:
Vegetative Structure:
Thallus is dichotomously branched dorsiventrally differentiated and innovating at the apex. It is corriaceous without distinct areolae on the dorsal surface. Ventral surface of the thallus lias two rows of scales and rhizoids which are unicellular, smooth-walled and tuberculate.
In T.S. through the thallus following layers can be noticed:
(a) Dorsal epidermal layer containing cells which are 4 – 6 angled and pores (a little elevated).
(b) Dorsal air chambers.
(c) Parenchymatous cell zone and
(d) Ventral surface layer with purple scales in one row on each side of the midrib and rhizoids (Fig 5.9).
Reproductive Structure:
Plants are monoecious or dioecious. Male receptable is sessile, cushion-like and situated at the apex of a lobe. It is somewhat oval to semilunar and surrounded by small scales. Female receptacle is situated terminally on ordinary lobes and stalked.
Stalk is surrounded at the base and apex by narrow scales/with a single rhizoidal furrow. Female receptable is conical or hemispherical and also divided up to the middle into 7-9 obtuse lobes with air spaces.
Sporogonium:
It possesses a spherical capsule, seta and foot. Capsule has a single-layered jacket, and dehisces irregularly at the apex. Spores are spherical, brown, reticulate – lamellate and about 65 – 75 µm in diameter. Elaters are with 2-3 spirals, coiled, 300 – 400 µm long (Fig 5.9).
Identification:
Thallus dorsiventrally flattened and prostrate, sporophyte simple and with limited growth, columella absent.
CLASS: HEPATICOPSIDA
Plant body prostrate, sex organs on dorsal surface, sporophyte devoid of columella or elaterophore.
ORDER: MARCHANTIALES
Sex organs develops in a cluster on a specialised stalk, sporophyte differentiated into foot, seta and capsule.
FAMILY: MARCHANTIACEAE
Plants with air-chambers and pores, ventral surface with scales, capsule not embedded in the thallus, Gemmae cup absent. Male receptacle sessile, female receptacle hemispherical, with 7-9 lobes.
GENUS: REBOULIA
9. Plagiochasma:
Vegetative Structure:
Thallus is long, lobed, and flat, dorsiventrally differentiated, dichotomously branched and with undulated margins. Apex of the thallus is notched. Dorsal surface is dark-green. Ventral surface is purplish and bears scales and rhizoids. Midrib is inconspicuous and gradually passing into the lamina.
In T.S. of the thallus, the following layers are noticed:
(a) Upper epidermis with simple pores,
(b) Dorsal air-chambers,
(c) Parenchymatous cell zone,
(d) Ventral layer with multicellular scales and rhizoids which are unicellular, smooth-walled and tuberculate.
Reproductive Structure:
Plants are monoecious. Receptacles are always located at apex to begin with, becoming dorsal by the formation of apical adventitious shoots. Male receptacle is formed one after another, or a male receptacle may be followed by a female receptacle. Male receptacle is sessile, horse-shoe-shaped and surrounded by linear scales. Air-chambers with simple pores lies between the antheridia.
Female receptacle is also sessile when young, but at maturity stalked. The stalk arises from the dorsal side of the thallus, and is devoid of rhizoidal furrow, but has scales at base and apex. Female receptacle is more or less concave on the dorsal surface, with barrel-shaped pores and is 2 – 9 lobed. It is surrounded by involucres which are large, inflated, bivalved and margin folded inwardly. Each involucre contains one archegonium.
Sporogonium:
With capsule, short seta and a foot capsule is spherical with single-layered jacket. Spores are yellowish and reticulate-lamellate. Elaters are short and bi-or trispiral.
Identification:
Thallus dorsiventrally flattened and prostrate, sporophyte, simple and with limited growth, columella absent.
CLASS: HEPATICOPSIDA
Plant body prostrate, sex organs on dorsal surface, sporophyte devoid of columella or elaterophores.
ORDER: MARCHANTIALES
Sex organs develops in a cluster on a specialised stalk, sporophyte differentiated into foot, seta and capsule.
FAMILY: MARCHANITACEAE
Plants with air-chambers and pores, ventral surface with scales, capsule in involucres, plants without gemmae cup, male receptacle sessile and horse-shoe-shaped, sessile receptacle distinctly dorsal.
GENUS: PLAGIOCHASMA
10. Pellia:
Vegetative Structure:
Plant body is thin, dorsiventral, prostrate, dichotomously branched, with somewhat wavy margin. The dorsal surface is almost smooth and a median midrib is prominent. On the ventral surface numerous smooth, unicellular rhizoids are borne from under the midrib.
In T.S. through the thallus, following layers can be noticed:
(a) Upper and lower epidermis are present lower epidermis is with numerous smooth rhizoids,
(b) In between the two epidermal layers there are compact parenchymatous, chloroplast containing cells with a few scattered fibrous cells. Usually the midrib portion is thicker (8 – 16 layers in depth) than margins (2-5 layers in depth) (Fig 5.11).
Reproductive Structure:
Plants are either monoecious or dioecious. In the dioecious forms, the male plant bears antheridia all along the dorsal surface of the midrib while the archegonia develop in a cluster just behind the growing tip on the dorsal side of the female plant. In monoecious forms, the antheridia are behind the archegonia.
The mature antheridium is globose with a jacket one cell in thickness and a multicellular short stalk. It lies at the bottom of the antheridial chamber which is open on the dorsal surface by a pore. The mature archegonium shows a venter containing the egg, a ventral canal cell and 4 to 6 neck canal cells.
Sporogonium:
Sporophyte is covered by involucre and calyptra. Each sporophyte has a distinct foot, seta and globose capsule. Capsule has two-layered jacket cells of outer layer larger with radial walls thickened and cells of inner layer with inner tangential wall thickened and numerous spores and elaters. There is a distinct elaterophore (formed by a group of elaters) at the base of each capsule (Fig 5.11).
Identification:
Thallus dorsiventrally flattened and prostrate, sporophyte simple and with limited growth, columella absent.
CLASS: HEPATICOPSIDA
Absence of air-chambers in the gametophytic tissue and scales and tuberculate rhizoids too, internal tissue differentiation absent, antheridia globose and long-stalked, capsule wall multilayered; foot and seta distinct.
ORDER: JUNGERMANNIALES
Gametophytic thallus, green, flattened and glossy, cells are chlorophyllous and homogenous type, sporophytes differentiated into foot, seta and capsule, capsule with distinct elaterophores at the basal part.
SUB ORDER: METZGERINEAE
Sporophyte bears globose capsule with spores, elaters and elaterophore, sporophyte jacket two-layered with characteristic wall thickening.
FAMILY: PELLIACEAE
Gametophyte usually thallose, prostrate, archegonia on dorsal surface of the thallus just behind the apical cell.
GENUS: PELLIA
11. Porella:
Vegetative Structure:
Plant body is flat, dorsiventral with a bi- or tripinnately branched leafy axis with no rhizoids in mature plants. There are 3 rows of leaves – 2 lateral and one smaller row on the ventral side termed amphigastria. Leaves are thin without midrib and one cell in thickness. Lateral leaves are two-lobed – upper larger lobe is antical lobe and the lower smaller lobe is the postical lobe or lobule. The arrangement of leaves is incubers.
In T.S. through the stem, there is an only epidermal and cortical cell layer. The peripheral cells of cortex are smaller with slightly thicker walls while the central cells are larger with thinner walls.
Reproductive Structure:
Plants are dioecious. The male plant is smaller with the antheridial branches projecting out at-sight angles from the axis. The leaves on the antheridial branch are closely imbricate and a single antheridium is borne in the axil of each leaf. The mature antheridium is globular with a long stalk. The jacket is one-layered, but the lower part is 2 – 3 layered.
The female plant bears archegonial branches with enlarged perichaetial bracts. The lower bracts form an involucre while the upper two coalesce to form a perianth within which the archegonia develop. A mature archegonium shows a venter with the egg, the ventral canal cell and a neck with neck canal cells (Fig 5.12).
Sporogonium:
Sporophyte consists of a spherical capsule, a short seta and a bulbous foot. The capsule wall is 2 to 5 layers thick. Inside the capsule there are a number of spores and elaters (Fig 5.12).
Identification:
Thallus dorsiventrally flattened and prostrate, sporophyte simple and devoid of columella.
CLASS: HEPATICOPSIDA
Absence of air-chambers in the gametophytic tissue, capsule wall multilayered foot and seta distinct.
ORDER: JUNGERMANNIALES
Usually the whole gametophytic body or at least the reproductive part foliaceous, archegonia formed apically.
SUB ORDER: JUNGERMANNINEAE
The whole gametophytic plant body foliaceous, leaves nerveless, on the ventral side prominent amphigastria present, sporophyte stalked and covered by conspicuous perianth which resembles the foliage leaves.
FAMILY: PORELLACEAE
Plant body flat with bi- or tri-pinnately branched leafy axis, ventral smaller row forming amphigastria.
GENUS: PORELLA
12. Metzgeria:
Vegetative Structure:
Thallus is membranous and usually dichotomously or sometimes pinnately branched with ventral innovations arising from the side of the midrib. Midrib is slender and sharply defined from the wings (wing of lone layer of cells). Usually hairs are commonly seen on the under surface of the thallus.
In T.S. through the thallus, it appears that the wing or lamina is one cell in thickness and about 12-14 cells wide on each side of midrib. The midrib portion is however 4-6 cells thick and 3-4 cells broad. It also bears the hairs, mostly all round (Fig 5.13).
Reproductive Structure:
Plants are dioecious. Gemmae are discoid to linear. Sex organs are developed on ventral branches. Antheridia are few, shortly pedicellate and globose. Female branches are curved into an obcordate involucre furnished with hairs. Perianth is absent.
Sporogonium:
It possesses an oval-shaped capsule, short seta and a foot. Capsule wall is 2 layered thick. Spores are small, spherical, smooth or minutely papillate. Elaters are free, long, attenuate, mono-spiral and reddish-brown in colour.
Identification:
Thallus dorsiventrally flattened and prostrate, sporophyte simple and devoid of columella.
CLASS: HEPATICOPSIDA
Absence of air-chambers in the gametophytic tissue, antheridia globose and long stalked, capsule wall multilayered, foot and seta distinct.
ORDER: JUNGERMANNIALES
Gametophyte thallose, dorsiventral and prostrate, archegonia on dorsal surface of thallus.
SUB ORDER: METZGERINEAE
Thallus membranous, sex organs on short branches, capsule oval, usually with 2 layered jacket, elaters tappering towards each end with spiral bands.
FAMILY: ANEURACEAE
Thallus membranous, with a sharply defined midrib and a lamina composed of one layer of cells, elaters free, long tapering at each end, mono-spiral type.
GENUS: METZGERIA
13. Anthoceros:
Vegetative Structure:
Thallus is sub-orbicular and variously lobed without a sharply defined midrib. Air-chambers and scales are absent, but slit-like pores and smooth rhizoids are present on the under surface of the thallus. Thallus is prostrate, dorsiventrally differentiated, rarely dichotomously branched and also has a dark-green colour.
In T.S. through thallus, there is very little tissue differentiation. It is composed of uniform, thin-walled, parenchymatous cells which are many cells deep in the middle. Epidermal cells are somewhat smaller and compact with chloroplasts. But the dermal cells are angular, larger with chloroplasts.
Chloroplasts are one in each cell and have pyrenoids. There are a few cavities inside the dermal zone which are full of mucilage and have blue green algal colonies i.e. Nostoc. The cavities open to the exterior through slit-like pores. Rhizoids are unicellular and smooth-walled (Fig 5.14).
Reproductive Structure:
Plants are dioecious or monoecious. Both antheridia and archegonia are embedded in the dorsal surface of the thallus along the midrib region. Antheridia arise in groups and are included in antheridial chambers. Archegonia are solitary and without air-chambers.
A mature antheridium shows a more or less slender stalk bearing a club-shaped or spherical antheridium which has a jacket one layer in thickness containing the androcytes inside. A mature archegonium has an egg, a ventral canal cell and 4 – 6 neck canal cells.
Sporogonium:
Mature sporophyte shows a bulbous foot, and slender, erect smooth cylindrical capsule standing out like a bristle from the thallus (2 to 15 cms. long). There is no seta but an intermediate zone of a few layers of meristematic cells in its place is present.
The base of the capsule is en-sheathed by an involucre up to a certain height. The capsule jacket is several layers in thickness. Spores and simple or branched pseudo elaters in alternating layers and central columella are present (Fig 5.14).
Identification:
Sporophyte with indefinite growth due to the presence of intercalary meristem at the base of capsule, sex organs embedded in the thallus, cells of thallus bear one chloroplasts in each with pyrenoid.
CLASS: ANTHOCEROTOPSIDA
Gametophytic thallus dorsiventrally flattened, internally gametophytic tissues not differentiated.
ORDER: ANTHOCEROTALES
Sporophytes are erect on the thallus, project out of the thallus, central columella present.
FAMILY: ANTHOCEROTACEAE
Thallus dark-greenish, prostrate and dorsiventrally flattened, spores black in colour.
GENUS: ANTHOCEROS
14. Notothylas:
Vegetative Structure:
Thallus is yellow-green-forming an orbicular or sub-orbicular rosette which has got a characteristic pleated appearance. Thallus is devoid of midrib.
In T.S. thallus shows the following zones:
(a) Epidermal layers with compact, chloroplast bearing cells.
(b) Cortical zone which is 6 – 8 cells deep in the middle and thinning out to 1 – 3 cells in the edges. Inside the cortical layers there are some cavities containing blue-green algae like Nostoc and Anabaena.
(c) At places ventral surface bears the rhizoids (unicellular and smooth-walled only).
Reproductive Structure:
Thallus may be monoecious or dioecious. Reproductive structures are embedded within the dorsal portion of the thallus along the median region. Antheridia are developed in groups of 2 – 3 within a cavity. Mature antheridium bears a short multicellular stalk and a jacket layer. Mature archegonium has an egg, venter canal cell and 4-6 neck canal cells. They are solitary and without air-chambers.
Sporogonium:
Sporophytes are slightly projecting out from the margin of the thallus and lie flat (horizontal) on the thallus. It has a foot and capsule, which contains multilayered jacket, spores and pseudo-elaters in alternate rows. Only some species have an ill-developed central columella. Meristematic tissue is present at the base of the capsule (Fig 5.15).
Identification:
Sporophyte with indefinite growth due to the presence of intercalary meristem at the base of capsule. Sex organs embedded in the thallus. Gametophytic thallus composed of single chloroplast bearing cells, each chloroplast with a large conspicuous pyrenoid.
CLASS: ANTHOCEROTOPSIDA
Gametophytic thallus dorsiventrally flattened, internally not differentiated.
ORDER: ANTHOCEROTALES
Sporophytes arc horizontal on the thallus, usually devoid of central columella. It is very small and scarcely projecting beyond the margin of the thallus. Thallus yellow-green, forming an orbicular or sub-orbicular rosette appearance.
FAMILY: NOTOTHYLACEAE
Gametophyte yellow-green forming orbicular or sub-orbicular rosette appearance with sporophyte on the margin of the thallus.
GENUS: NOTOTHYLAS
15. Sphagnum:
Vegetative Structure:
Plant body is erect, leafy, and bears rhizoids at the base (when young). The stem has whorls of lateral branches at intervals. Leaves are small, thin without midrib and spirally arranged on the axis. The main stem has fewer leaves. The leaves are sessile ovate-elongate, with smooth margin and acute apex.
In T.S. through the stem, the following layers can be noticed:
(a) An en-sheathing cortex of large hyaline cells. Cortex is multilayered on the main stem and one-layered on branch stems.
(b) Internal to the cortex is the central cylinder formed by smaller, vertically elongated cells.
(c) In addition, there are a few species where in the cortical layer there may be the presence of retort cells.
Leaves show: –
(a) Hyaline cells and
(b) Chlorophyllose cells.
Hyaline cells are large, rhomboidal with spiral thickening bands and simple pores. The chlorophyllose cells are smaller, long, narrow and remain lining the hyaline cells. They have chloroplasts.
Reproductive Structure:
Plant body may be monoecious or dioecious. Antheridia and archegonia are borne on special separate antheridial and archegonial branches. Antheridial branches are lateral but archegonial branches may be lateral or apical in position.
Antheridial branch has a long axis with spirally arranged leaves and antheridia lying in between them. Antheridia are globose and long-stalked with a single-layered jacket. Archegonial branch has a few large perichaetial leaves enclosing three archegonia. A mature archegonium shows a stalk, a twisted neck 8-9 neck canal cells, a ventral canal cell and an egg.
Sporogonium:
The mature sporophyte shows a spherical capsule and a bulbous foot connected by a very short neck. The whole sporophyte is covered by calyptra and perichaetial leaves. Capsule shows a jacket of 4 to 6 layers and the spore sac full of spores overarches the dome-shaped columella. The upper part of jacket forms an operculum with an annulus. The capsule is raised above by a long seta-like gametophytic structure called pseudopodium (Fig 5.16).
Identification:
Presence of leafy gametophyte with multicellular rhizoids having oblique cross-walls. Capsule has many layered jacket, spore sac devoid of elaters, columella, annulus and operculum present.
CLASS: BRYOPSIDA
Leaves without midrib and composed of two markedly different types of cells, chlorophyllose cells and hyaline cells, antheridia borne axially but archegonia borne in terminal position, Capsule opens by an operculum but lacks peristome.
SUB CLASS: SPHAGNIDAE
Single order.
ORDER: SPHAGNALES
Single family.
FAMILY: SPHAGNACEAE
Single genera.
GENUS: SPHAGNUM
16. Pogonatum:
Vegetative Structure:
Plant body is erect, somewhat rhizomatous and stem is covered by spirally arranged leaves. Numerous rhizoids develop from the base of the stem. The rhizoids are multicellular with oblique cross walls. Leaves are spirally arranged, more crowded and larger near the apex. The base of the leaf is broad, partly sheathing and pale. Leaves are gradually tapering, with serrate margin, acute apex and a midrib.
In T.S. through the mature stem, following layers of tissues are noted:
(a) Outermost single-layered epidermis with thick-walled cells.
(b) Cortical layers – outer thick-walled cortical zone and inner thin-walled cortical zone with leaf traces.
(c) Central core of specialised cells – starch containing leptoid cells and thick-walled hydroid cells.
A T.S. of leaf shows the midrib with patches of thick-walled cells and sectional view of the
lamellae – each 4 or 5 cells high. The top rows of cells of the lamellae differ from species to species.
Reproductive Structure:
Most of the species are dioecious. In male plant, the top leaves are specialised; coloured red or orange and form something like an involucre which is called perichaetium. Within the perichaetium, there is a cluster of antheridia and filamentous paraphyses.
The mature antheridium is a club-shaped structure with a short stalk and one-layered jacket. In female plant archegonial cluster develops at the tip. This cluster is surrounded by perichaetial leaves. There are mostly 3 archegonia in a cluster and some paraphyses. Each archegonium has stalk, venter, long neck, egg, ventral canal cell and neck canal cells (Fig 5.17).
Sporogonium:
Sporophyte consists of foot, seta and capsule. T.S. of capsule shows a wall (several layers thick), spore sac containing spores which is suspended in an air-chamber with trabeculae and columella. The columella extends upwards and forms an apical epiphragm (tympanum) bearing peristome with a ring of 32 short teeth.
Peristome is covered by operculum which is connected to the capsule by a diaphragm. Each peristome teeth is solid, formed by bundles of fibrous cells. Peristome teeth are nematodontous (solid, worm-like) and haplolepideous (in a single ring). The calyptra is deciduous. The operculum is conical and leaked. (Fig 5.17).
Identification:
Presence of leafy gametophyte with multicellular rhizoids having oblique cross walls; capsule with heavy layered jacket, columella.
CLASS: BRYOPSIDA
Seta well-developed, pseudopodium absent, peristome and operculum present.
SUB CLASS: BRYIDAE
Peristome nematodontous.
SECTION: NEMATODONTEAE
Peristome teeth solid and arranged in a single compact row, tips of all teeth remain attached to the drum-like top-tympanum formed out of the top cells of the columella.
ORDER: POLYTRICHALES
Gametophytic plant body tall, perennial, with narrow leaves, capsule erect, peristome teeth 32 to 64 in number.
FAMILY: POLYTRICHACEAE
Plants body is erect, leafy and dioecious. Presence of specialized stem core tissue – leptoids and hydroids, peristome teeth 32 in number and arranged in a ring, capsule round with angular columella in T.S.
GENUS: POGONATUM
17. Taxithelium:
Vegetative Structure:
Plants grow on tree trunks. The stem is pleurocarpic, creeping, branching profusely and pinnately, and forming a dense yellowish-green mat on the tree. Leaves are small, veinless, deeply concave, broadly ovate, bluntly acute and uniformly and densely surrounding the branches, so that the branches do not appear flat.
In T.S. through stem the following layers are noted:
(a) Epidermal layers,
(b) Cortical layers and
(c) Central core of specialised cells.
Leaves are one cell thick. Cells are papillose, elongate-rhomboid except at the base on two sides where there are two patches called alars, each composed of a few quadrate cells.
Reproductive Structure:
The plants are monoecious but antheridia and archegonia are borne on separate small side shoots. Sex organs are formed in clusters at the tips of the branches and covered by perichaetial leaves. Mature antheridia and archegonia are intermingled with paraphyses.
Sporogonium:
Sporophyte has a small foot, a long seta and an oval capsule. The capsule is asymmetrically bent and provided with a conical operculum. In T.S. through capsule, there is a thick jacket, spore sac and columella, diaphragm with arthrodontous, diplolepideous metacranoid rings of peristome teeth. Peristome teeth curl out exposing the spores when dry (Fig 5.18).
Identification:
Presence of leafy gametophyte with multicellular rhizoids having oblique cross-wall, capsule with many layer, columella, annulus and operulun.
CLASS: BRYOPSIDA
Seta well developed pseudopodium absent, peristome and operculum present.
SUB CLASS: BRYIDAE
Peristome teeth thin, membranous and articulate.
SECTION: ARTHRODONTEAE
Peristome teeth in two rings.
SERIES: DIPLOLEPIDEAE
Exostome teeth alternating with endostome teeth.
SUB SERIES: METACRANOIDEAE
Pleurocarpous, diplolepideous mosses with metacranoid peristome.
ORDER: HYPNOBRYALES
Sporophyte with small foot, a long seta and an oval, asymmetrical sent capsule.
FAMILY: SEMATOPHYLLACEAE
Plants growing on the trunks of trees, stem creeping, branching profuse and pinnate, alar cells present, peristome teeth curl out.
GENUS: TAXITHELIUM
18. Funaria:
Vegetative Structure:
The plant body is erect, branched with spirally arranged leaves. The leaves are more crowded near the apex where they appear like a rosette though actually arranged in three rows. Leaves are sessile, attached to the stem by a broad base, ovate-elongate, pointed at the apex and with a smooth margin. The plant bears rhizoids at the base.
Rhizoids are multicellular with oblique cross walls. A T.S. of the stem shows a small central strand of long, narrow, colourless, thin-walled cells devoid of protoplasm.
This is encircled externally by a cortex of chloroplast containing parenchymatous cells. The cortex also bears the leaf traces. The outermost layer is epidermis. The cross-section through leaf shows a well-defined midrib and one-layered lamina. Cells are elongated and thin-walled.
Reproductive Structure:
Plants are monoecious, the main sheet of the plant bears the antheridia. The female branch develops as a side-shoot. These shoots are terminated by clusters of antheridia or archegonia surrounded by perichaetium. The paraphyses with swollen tips are intermingled with sex organs. (Structure of sex organs – as in Pogonatum).
Sporogonium:
It has a foot, a long seta and a capsule. The mature capsule is pear-shaped, almost horizontal and asymmetrical. The lowermost part is apophysis which connects the seta below. In T.S. it shows a thick wall, spore sac suspended in an air cavity and attached to the wall by trabeculae, columella, diaphragm and annulus with peristome teeth. The jacket wall bears stomata in the apophysis region. The peristome teeth are 32 in number and arranged in two rows of 16 each.
The outer teeth are thick-walled, larger and brownish in colour and with transverse lars at the tip. The peristome teeth are arthrodontous, diplolepideous and epicranoid i.e. the outermost cells of the capsule apex form a dome-shaped operculum which keeps the teeth covered. The spores are small, round and smooth walled. Calyptra is small, hood-like and deciduous. (Fig. 5.19).
Identification:
Presence of leafy gametophyte with multicellular rhizoids having oblique cross-wall, capsule with many layer jackets.
CLASS: BRYOPSIDA
Seta well-developed, pseudopodium absent, peristome and operculum present.
SUB CLASS: BRYIDAE
Peristome teeth thin, membranous and articulate.
SECTION: ARTHRODONTEAE
Plants radially symmetrical, sporophyte well-differentiated, acrocarpous, diplolepideous, epicranoid.
ORDER: FUNARIALES
Peristome teeth 32 in number, arranged in two rows – outer (exostome) consists of 16 and inner (endostome) consists of 16 teeth; inner teeth thin and outer thick and vertically striate.
FAMILY: FUNARIACEAE
Peristome teeth in two rows – 16 in each row, outer teeth thick with transverse bars, capsule asymmetrical, nodding, spore small, rounded, calyptra deciduous and hood-like.
GENUS: FUNARIA
19. Bryum:
Vegetative Structure:
The plant is densely tuffed, slender and growing on damp walls. It is bright to dull green in colour. Stem is often branched at base. Leaves are lanceolate to ovate and long acuminate. Leaf cells are thin to thick-walled, narrow rhomboid to hexagonal. Perichaetial leaves are also shorter and triangular. Plants are dioecious – male plants are slender, long with pseudo-laterally placed antheridium.
Reproductive Structure:
Capsule is red to purple, pendulous thick and cup shaped. Capsule mouth is wide and operculum big with 2-3 rowed annuluses. Peristomes are arranged in two rows – outer teeth broad, lanceolate; but inner teeth lyaline and yellowish. Spores are rounded (7.6 to 11.4 µm in diameter). Exostome and endostome teeth are alternate each other.
Sporogonium:
Sporophyte is orange-coloured with distinct ovate capsule and erect seta. Capsule bears swollen apophysis. The peristome is arthrodontous diplolepideous and metacranoid with two rings of teeth of equal size. The outer ring is deeply coloured while the inner ring is hyaline with cilia (Fig 5.20).
Identification:
Presence of leafy gametophyte with multicellular rhizoids having oblique cross-wall, capsule with many-layer jacket.
CLASS: BRYOPSIDA
Seta well-developed, pseudopodium absent, peristome and operculum present.
SUB CLASS: BRYIDAE
Peristome teeth thin, scaly, formed by 2 layers of cells, articulate.
SECTION: ARTHRODONTEAE
Peristome teeth in 2 rows, exostomes and endostome teeth alternates.
ORDER: EUBRYALES
Single family.
FAMILY: BRYACEAE
Capsule orange-coloured, with swollen apophysis; peristome metacrenold.
GENUS: BRYUM
20. Fissidens:
Vegetative Structure:
Plant body is short, erect, un-branched, acrocarpic. Rhizoids are present at the base of the stem. Leaves are distichous, sessile, and alternate, with brown to yellowish midrib. There is also the presence of paired sheathing, lamini attached to the leaves. Leaves are composed of elongated cells. Leaf margin is smooth.
Reproductive Structure:
Plants arc dioecious, both male and female plants arc terminated by sex organs encircled by pcrichactial leaves.
Sporogonium:
Mature sporophyte is with long seta, foot and capsule in terminal position. Capsule is horizontal, symmetrical, oblong, and brown to deep red in colour at maturity. There is one ring of 16 peristome teeth (hcpalolepideous) each of the teeth being split into two (dicranoid) almost up to the base. The teeth are arthrodontous (Fig. 5.21).
Identification:
Presence of leafy gametophyte with multicellular rhizoids having oblique cross wall, capsule with many-layer jacket.
CLASS: BRYOPSIDA
Seta well-developed, pseudopodium absent, peristome and operculum present.
SUB CLASS: BRYIDAE
Peristome formed by 2 or 3 layers of membranous or scaly plate-like layers, peristome articulated by transverse striations.
SECTION: ARTHRODONTAE
Plants acrocarpous; 16 dicranoid peristome teeth in one ring.
ORDER FISSIDENTALES
Leaves distichous vertically placed, with sheathing lamini; capsule lateral to terminal; peristome dicranoid.
FAMILY FISSIDENTACEAE
Peristome teeth split into two almost up to the base, with longitudinal strips; presence of sheathing lamini.
GENUS: FISSIDENS
