orders and families. Series (ii) Heteromerae: The flowers are hypogynous, superior ovary and with more than two carpels. Heteromerae includes orders and families. .
Totally unrelated plants were kept in a single group, whereas closely related plants were placed in widely separated groups. Example: a. Zingiberaceae of monocotyledons and Anacardiaceae of dicotyledonous were placed under the class Monandria since these possess single stamens. b.
Prunus was classified along with Cactus because of the same number of stamens. No attempts were made to classify plants based on either natural or phylogenetic relationships which exist among plant groups. . .
Natural system Botanists who came after Linnaeus realised that no single character is more important than the other characters. Accordingly an approach to a natural system of classification sprouted in France. The first scheme of classification based on overall similarities was presented by Antoine Laurent de Jessieu in . Bentham and Hooker system of classification Figure .
: George Bentham and J.D. Hooker A widely followed natural system of classification considered the best was proposed by two English botanist George Bentham ( – ) and Joseph Dalton Hooker ( – ). The classification was published in a three volume work as “ Genera Plantarum ” ( – ) describing families and genera and The Bentham and Hooker system of classification is still supposed to be the best system of classification. It has been widely practiced in colonial countries and herbaria of those countries were organised based on this system and is still used as a key for the identification of plants in some herbaria of the world due to the following reasons: • Description of plants is quite accurate and reliable, because it is mainly based on personal studies from actual specimens and not mere comparisons of known facts.
• As it is easy to follow, it is used as a key for the identification of plants in several herbaria of the world. Though it is a natural system, this system was not intended to be phylogenetic. . .
Phylogenetic system of classification The publication of the