Epiphyte

     'Epiphyte', means an organism that grows upon another organism but is not parasitic on it. The epiphytic vegetation that often forms mattresses on the barks of trees is composed, in this instance, of lichens, mosses, a clubmoss and flowering plants such as an orchid etc. Epiphytes, which have no direct contact with the forest floor, obtain water from the humid air of the canopy, as well as directly from the rain and they obtain minerals from dust and the surface of the plants on which they grow. The mattresses of epiphytes are displayed in the Systematic Botany Gallery.

Introduction to Bryophytes

    The division 'Bryophytes' is a small group of terrestrial plants numbering 20,000 to 25,000 species. As a group, they have worldwide distribution occuring in all climates of the earth. In general, the plants grow in moist situations. From the point of view of their evolution the bryophytes are lower than that of pteridophytes and phanerogams. Bryophytes are land inhabiting plants. Water is still needed for the movement of the gametes of bryophytes and in their vegetative structure, they have adapted themselves to a terrestrial life. Hence the bryophytes are called 'Amphibians of the plant kingdom'. The plant body is a thallus, generally small and attaining a length of a few inches. The plant usually grows attached to the soil by branches of the plant body called 'rhizoides'. 'Bryologists', generally agree that those members of the bryophyta exhibiting considerable external dissection of the thallus present a 'leafy' apperance and are primitive whereas those with a less-dissected apperance are highly specialized and advanced. Models of marchantia thallus, herbarium of mosses and their wet specimens are exhibited in the Systematic Botany Gallery.

Moss

     'Moss', belongs to the division 'Bryophytes'. Bryophytes are amphibians of the plant kingdom. Moss usually occur as green patches on damp walls, rocks and tree trunks and on the forest floor. The dependence of moss on humid environment can be related to two important features: (a) the sperms are flagellate and need water to swim to the egg cell in the archegonium and (b) in the absence of the vascular tissue, the plants do not have an efficient transport system and consequently water is absorbed through the leaf surface.

     The life cycle of a moss plant consists of two multicellular phase, an independent, leaf gametophytic phase and a partly dependent, sporophytic phase, which dominate the life cycle. A 'gametophyte' is a small plant and it has a tiny stem bearing small green leaves. Unlike higher plants, a moss plant lacks the vascular tissue in the leaves and stem. The plant is anchored to the substrate by means of rhizoids arising from the base of the stem. They are reproduced  vegetatively and sexually.

Moss

     The 'Moss' are a large group of plants, which constitute higher 'Bryophytes'. They are worldwide in distribution, growing in every kind of habitat from hydrophytic to xerophytic; most of them are found in moist and frequently in shaded locations. Moss plants vary in size from specimens scarcely visible without the aid of a hand lens to large forms. The conspicuous part of the moss plant consists of the more or less erect caleuid (stem) which bears expanded phyllids (leaves). The stem  may be branched or unbranched, in general they are more slender and delicate. The root like strands known as rhizoids, anchor the plant to the substratum. The leaf stems are known as the 'gametophores' because they bear the 'gamatangia' and the gamets. After the fertilisation, the 'sporophyte' is developed at the apex or on the side of the gametophore. The outstanding structural feature is the development of protonema in early stages of the life cycles.