Thallophyta
Plant body a thallus, with no distinction of stem, root and leaf. Individuals mostly small with simple organization, many microscopic.
(a) ALGAE. Organisms possessing chlorophyll and sometimes additional pigments.
(1) Euglenophyceae Motile protoplasts with no cellulose wall. No sexual reproduction.
(2) Chlorophyceae Cellulose wall present. Chlorophyll only. Fresh-water and marine.
(3) Cyanophyceae Blue-green colour due to phycocyanin. Fresh-water and marine.
(4) Phaeophyceae Brown colour due to fucoxanthin. Exclusively marine.
(5) Bacillariophyceae Unicellular forms with silicified cell walls. Brown colour due to diatomin. Fresh-water and manne.
(6) Rhodophyceae. Red colour due to phycoerythrin. Predominantly marine.
(b) FUNGI: Organisms devoid of chlorophyll; either saprophytic or parasitic.
(1) Archimycetes Thallus a naked mass of protoplasm. Asexual reproduction by spores formed in sporangia. Sexual reproduction by motile gametes.
(2) Phycomycetes Thallus a mycelium of non-septate hyphae.
Asexual reproduction by spores formed in sporangia, or by conidiospores. Sexual reproduction by variously formed gametes.
(3) Ascomycetes Mycelium of septate hyphae. Asexual reproduction by conidiospores. Sexual reproduction resulting in ascospores formed in sac-like cells (asci) which form a fruiting body.
(4) Basidiomycetes Mycelium of septate hyphce. Asexual reproduction occasionally by conidiospores. Sexual reproduction resulting in basidiospores borne on short stalks from special cells (basidia) developed on a fruiting body.
(c) BACTERIA: Minute unicellular organisms, usually devoid of chlorophyll and without a fully organized nucleus. Reproduction by binary fission and by spores. Sexual reproduction doubtful.
(d) LICHENES Compound organisms consisting of fungal and algal partners. Reproduction fungal (mostly Ascomycetes).
Charophyta
Thallus jointed, branched, attached at the base; conisting of large coenocytes, containing chlorophyll. Sexual reproduction by antherozoids in antheridia and oospheres in oogonia. Fresh-water.
(a) CHARALES The sole order. Characters as above.
Bryophyta
Terrestrial or fresh-water. Gametophyte either a thallus or differentiated into stem and leaves, attached by rhizoids but without true roots. Sexual reproduction by antherozoids in antheridia and oospheres in archegonia. Sporophyte permanently attached to the gametophyte. Homoporous.
(a) HEPATICAE Gametophyte thalloid or with leafy stem. Sex organs apical or dorsal. Sporophyte usually non-chlorophyllous.
(b) MUSCI Gametophyte with leafy stem. Sex organs apical or lateral. Sporophyte usually chlorophyllous.
Pteridophyta
Mainly terrestrial. Sporophyte with stem, roots and leaves. Vascular tissue present. Spores produced in sporangia. Gametophyte a small prothallus bearing antheridia and archegonia.
(a) PSILOPSIDA Sporophyte with small leaves (microphyllous) or none.
Homosporous. No true roots. Sporangia free or united into synangia, terminal or on specialized branches. Gametophyte in living forms reduced, saprophytic.
(b) LYCOPSIDA Sporophyte with numerous, usually small leaves
(microphyllous). Homosporous or heterosporous. Sporangia free, borne on or axillary to sporophylls. Gametophyte reduced, saprophytic or enclosed in the spores.
(c) SPHENOPSIDA Sporophyte with jointed stems and small leaves In whorls (microphyllous). Homosporous. Sporangia clustered, in terminal strobili. Gametophyte green.
(d) PTEROPSIDA Sporophyte with large leaves (megap~lous). Homosporous or heterosporous. Sporangia clustered on foliar organs. Gametophyte either green, or reduced and enclosed in the spores.
Spermatophyta
Sporophyte with stems, roots and leaves. Vascular tissue present. Heterosporous. Microspores (pollen grains) and megasporse (embryo sacs) produced in distinctive sporangia. Megasporangia with integuments, developing into seeds. Gametophytes extremely reduced, enclosed in the spores.
(a) PTERIDOSPERMAE Leaves fern-like. Sporangia borne on normal or only slightly reduced leaves, not aggregated into flowers.
(b) GYMNOSPERMAE Sporangia aggregated into strobili (cones), each usually containing only one type of spore. Megasporangia exposed.
(c) ANGIOSPERMAE Sporangia either in separate or in the same flowers.
Megasporangia enclosed in carpels, which ripen into fruits.
(1) Dicotyledons Embryo with two cotyledons. Leaves mostly net-veined.
(2) Monocotyledons Embryo with one cotyledon. Leaves mostly parallel-veined.
