HUTCHINSON SYSTEM OF CLASSIFICATION DR. PIYUSH KUMAR RAI - PowerPoint PPT Presentation

HUTCHINSON SYSTEM OF CLASSIFICATION DR. PIYUSH KUMAR RAI DEPARTMENT OF BOTANY SEMESTER - IV PAPER - BOT CC410 PATNA WOMEN’S COLLEGE PATNA UNIVERSITY, PATNA

JOHN HUTCHINSON (1884-1972) A British Botanist Who was Associated with the Royal Botanic Garden at Kew, England

• He proposed a system of Classification which was based on Bentham and Hooker and Bessey. • It is the best know and accepted Phylogenetic system of classification. • He orginally presented the system in his two volume work The families of flowering plants.

• Vol – 1 : Dealing with the Dicotyledons in (1926) • Vol- 2 : Dealing with the Monocotyledons in (1934) • It was revised in 1948 in his British Flowering Plants and again in his second edition of The Familier of Flowering plants.

PRINCIPLE ADOPTED BY HUTCHINSON (1959) • Evolution of both upward and downward . • Evolution does not necessarily involve all organs of the plant at the same time . • Evolution has generally been consistent • Tree and shrub are probably more Primitive than herbs .

• Perennial are older than biennial . • Aquatic flowering plants are as rule more recent than terrestrial and the same may be said of epiphytes, saprophytes and Parasities . • Collateral vascular bundles arranged in a cylinder.

• Leaves precede compound leaves. • Bisexual precede unisexual flower and the dioecious is probably more recent than the monoecious condition. • Solitary flower is more Primitive and form it syncarpy has resulted .

OUT LINE OF HUTCHINSON CLASSIFICATION

• Phylum : Angiospermae • Sub phylum l : Dicotyledons • Division I : Lignosae (54 order) : Order 1 Magnoliales- Order 54 Vertenales. • Division ll : Herbaceae : Order 55 Ranales- order 82 Lamiales.

• Subphylum Il : Monocotyledons • Division l: Calyciferae (12 order) : Order 83 Butomater to order 94 . • Division ll: Corolliferae (14 order) : order 95 liliales to order 108 orchidales • Division lll: Glumiflorae (3 order) : order 109: juncales to order 111 Graminales.

MERIT OF HUTCHINSON SYSTEM OF CLASSIFICATION • The families and order in the this system are if small size and comprise only very closely texa . • This system is in conformity with the modern view of the Phylogeny of Angiosperm as it considers the Ranales and Mognoliales as the starting point among dicot.

• In this system monocot are discussed after dicots . • Reshuffling or genera and families. • Placing of gymnosperm before angiosperms in flowering plants .

DEMERITS OF HUTCHINSON SYSTEM OF CLASSIFICATON • Dicots have been divided into two major groups Lignosae and Herbaceae in this system . This kind of classification is outdated as the habit used to be the main basis of classification in the past era of Aristotle. • Secondly it also the families that have close affinities. • This system is not much utility from the point of view of plant classification.

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