Englar and Prantl system of classification:
Two German botanists Adolph Englar (1844 – 1930) and Karl Prantl (1848 – 1893) published their classical treatise “Die Naturalichen Pffanzen families” covering the entire plant kingdom nearly half a century ago (1887 – 1909). While the authors named did much of the work o the flowering plants many sections throughout the plant kingdom were assigned to other specialists. Englar and Prantl system is a development of that Eichler and follows it in many respects. It has replaced Benthem and Hooker system in the continent of Europe and America as the latter is defective in as much as the families under Monochlamydeae show close affinities with those placed in the other groups such as Polypetalae.
According to Englers’ system Monochlamydeae is completely abolished as such and its families are distributed in large series called Archiochlamydae. This system now dominates the field of systematic Botany, though not to the exclusion of others. Since it was proposed subsequent of to acceptance of the theory of descent, it throws light on phylogeny of various groups and traces the increasing complexity of the flowers particularly their necessary whorls. According to this system most primitive types of flowers has no perianth then only one whorl and in the highest type two whorls of perianth. In the latter case who whorls may be indistinguishable (homoiochlamydous) or distinguishable into calyx and corolla (heterochlamydeous).
The gamopetalous condition according to this system is considered more advanced than polypetalous condition and the monocotyledons are placed before dicotyledons. Besides this evolution is also traced from hypogyny to Epigyny through intermediate forms of perigymy and from an indefinite number of stamens and carpels to definite number. Monocotyledons have been classified into 11 orders and 45 families and Dicotyledons into 44 orders and 261 families.
Hutchisons’ system of classification: The families of flowering plants by J. Hutchison of Royal Botanical Gardens, kew England was published in two volumes, the first dealing with dicotyledons appeared in 1926, the second one Monocotyledons appeared in 1934, its underlying principles are more like the Besseyan system than Englerian system is based on the assumption that the plants with sepals and petals associated with other floral and anatomical characters are the primitive and more ancient than the plants without sepals or petals. Free parts are considered more primitive than the connate or adnate parts.
The spiral arrangement of floral parts as also numerous free stamens and hermaphrodite condition are more primitive than unisexual flowers with fewer connate stamens and floral parts arranged in cyclic manner. The monocotyledons follow dicotyledons in this system. On the whole the arrangement follows that of Benthem and Hooker. Even though some may doubt the wisdom of maintaining distinction between the various types of woody and herbaceous plants, all agree that Huchison’s system shows advance step in phylogenetic conception.
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