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Introduction
Systematic Botany deals with the classification of plants. The
study is based upon the structural resemblance of plants and is helpful in identifying them.
The resemblance are brought out by describing, naming and arranging the plants in a methodical
manner for which a thorough knowledge of morphology is necessary. At first people took
interest only in useful medicinal and crop plants. This naturally left out of consideration
very many plants, which were not known to be either medicinal or otherwise useful. Later on,
plants were classified into herbs, shrubs and trees. Still later on, Linnaeus, hailed as the
father of systematic botany, gave out a classification based on the nature of stamens and
pistils of flowers. This system of classification is also known as the 'sexual system'.
There are a number of systems of
classification named after the botanists who gave them out. The current systems of
classification are those of Benthem and Hooker, Engler, Bessey, Hutchinson and Tippo. The
system of Benthem and Hooker is often followed in British Commonwealth, Engler's in Europe and
the Eastern half of U.S.A. and it is true, that none of them can claim to be a perfect system.
It may be stated that all of them serve as good keys for the purposes of identification of any
given plant.
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Dalbergia latifolia
Rose Wood
'Dalbergia latifolia' commonly called as 'Rose wood', belongs to the family
'Fabaceae'. It is a deciduous tree, attaining a large size in South India and also in Eastern
Bengal and Central India. This tree grows extensively and vigorously in the Deccan, Konkan and
Gujarat forest. The plant timber is strong, very hard, close-grained and of a purple black
colour which gives a valuable furniture wood and employed for cart-wheels, agricultural
implements, gun-carriages. It is good for carving and fancy work and used for the handles of
knives, kukris and other arms. It has been employed for sleepers. The 200 years old cross
section of the wood is exhibited in the Systematic Botany gallery. It was gifted by the
Maharaja of Travancore in the year 1880.
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Introduction
to Fungi
Fungi are
achlorophyllus, heterotrophic, eukaryotic organisations. They are as distinct from algae and
from plants as they are from animals. The study of fungi is called 'Mycology'. They occur in
all types of climate. They are primarily terrestrial but some are living in water. Most of the
fungi have multi-cellular structures but some are unicellular in nature. All fungi are
heterotropic, in obtaining their food, they function either as saprobes (living on organisms)
or as mutualistic symbionts or as parasites (living on other organisms). The fungi reproduce
asexually (without involving the fusion of sex cells) as well as sexually. They affect us
directly by destroying our food, fabrics, leather and other similar articles, by causing many
common and dangerous diseases of man, animals and plants. On the contrary, preparation of
bread, wines, bears, etc., which involve fermentation cannot be complete without these tiny
micro-organisms. Use of fungi in the preparation of many antibiotics, organic acids, vitamins,
hormones, enzymes and drugs, is notable. The amazing 'Toadstool fungus', and 'Bracket fungus'
are kept in the reserve collection.
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Polyporus
Bracket Fungi/Pore Fungi
It is a fungus belonging to the
family 'Polyporaceae', division 'Basidiomycotina'. Commonly called 'pore fungi'. These fungi
are so called because their hymenial layer lines the inner surface of tubes, all of which open
on the under surface of the pileus lending it a porous appearance. When young, the basidiocarp
is soft but as it grows older, it becomes hard, tough, leathery and usually
bracket-shaped and hence the name, 'Bracket-fungi', is given.
The polyporus grows parasitically
on roots, trunks and branches of trees. Quite often, they are seen to grow on dead or fallen
tree trunk. Many species of polyporous are wood rotters, sometimes causing severe economic
losses especially if the tree logs are left damp.
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Agaricus
Toadstool / Mushroom
'Agaricus' is a saprophytic fungus,
making its appearance just after the rains, on moist soil rich in organic matter and on moist
wood. The visible part of the fungus is an umbrella-like structure which is, really the fruit
body of the fungus and is popularly called 'Mushroom' (or) 'Toadstool'. It consists of a
central erect, thick stalk known as the 'Stipe' and a broad, expanded, cap like portion on the
top of the stipe known as the 'Pileus'. The upper side of the pileus is convex, while on the
lower side are found numerous, thin, plate-like structures that start from the stipe and
radiate outwards to the edge of the pileus. Each plate is called a 'gill plate'.
Some of the mushrooms are edible
and are cultivated. These are white in colour. Others have a brightly coloured pileus- red,
yellow or orange with black dots or white streaks. These coloured ones are generally
poisonous. The saprophytic forms on wood cause decay of wood.
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| Plant Fossils
The study of the plant kingdom of the
earliest period of the earth's history is an interesting and complicated field, which is known
as 'Paleobatony'. The most important material subjects of these studies are the fossil remains
of past geological ages. They are available in the form of dendrolites, carbonised,
mineralised and petrified remains of plants and in the form of inclusions in amber spores (or)
pollen grains.
Today, Paleobotany gives a clear survey
of the development of the plant kingdom and of the flora of the individual periods of the
history of the earth. Some of the fossils are kept on display.
Plant impression on white shale :
It is an unidentified plant fossil impression on white shale collected from a clay pit near
the PWD Rest house in Sriperumbudur (Tamilnadu).
Fragments of Elatocladus conferata :
It belongs to an important group of 'Jurassic' plants. It is a conifer fossil representing
an impression by a twig with leaves found in the clay bed near Sriperumbudur
(Tamilnadu).
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Next Gallery
Systematic Botany