Mrs. Shuba S V

Lecturer,

Department of Botany,

BMS College for Women

CONTENTS

Chapter – 03

Part - 1

❖Bentham and Hooker System of Classification.

BENTHAM AND HOOKER’S SYSTEM:•This system was represented by two scientists in a book with three volumes named as “Genera Plantarum”•George Bentham (1830-1884) was an English scientist and a well-trained botanist.•Sir Joseph Hooker (1817-1911) was Director of Royal Botanical Garden at Kew, was more plant explorer.•Bentham and Hooker’s classification deals with seed and flowering plants.•It described 202 families grouped into cohorts.•Total no of spp was some 97,205 of seeded plants.•They divided seed plants of Phanerogams into three categories:(i) Dicotyledons(ii) Gymnospermae(iii) Monocotyledons

Thalamiflorae Disciflorae Calyciflorae

• Flowers are Hypogynous

• Ovary is superior

• Flowers are Hypogynous

• Ovary is superior

• Flowers are Perigynous or Epigynous

• Ovary Inferior

• Well developed receptacle • A disc always surrounds the ovary • Sepals united and adnate to ovary

• Sepals are free

• Stamens indefinite

• Sepals are free/sympetalous

sometimes adnate to ovary

• Stamens definite; as many as or

twice the petals

Inferae Heteromerae Bicarpellatae

• Stamens as many as petals and

alternating with them

• Flowers are hypogynous • Flowers are hypogynous

• Stamens as many as corolla lobes

and alternate with stamens

• Plants have Inferior ovary • Plants have superior ovary

• Multicarpellary ovary

• Plants have superior ovary

• Ovary is bicarpellary

Salient Features

❖ Plants are grouped into Dicotyledons, Gymnosperms and

Monocotyledons.

❖ Ranales are placed in the beginning and grasses at the end.

❖ Gymnosperms are placed between Dicots and Monocots.

❖ Dicots are divided into Polypetalae, Gamopetalae and Monochlamydae.

❖ Monocots are divided into 7 series.