Q.How many families were described by Bentham and Hooker classification?

The realisation that no single character (like stamen count) deserves more weight than any other sparked the natural-classification approach in France; the first such scheme, based on OVERALL similarity across many characters, was presented by Antoine Laurent de Jussieu in 1789. The best-regarded and most widely followed natural system was proposed by English botanists George Bentham (1800-1884) and Joseph Dalton Hooker (1817-1911) in the three-volume Genera Plantarum (1862-1883), describing 202 families, 7,569 genera and 97,205 species. Seed plants split into three classes: Class I Dicotyledonae (two cotyledons, reticulate venation, tap root, tetra-/pentamerous flowers), itself split by corolla type into Sub-class Polypetalae (free petals) - further split by thalamus SHAPE into Series Thalamiflorae (dome/conical thalamus, superior ovary), Disciflorae (disc-shaped thalamus, superior ovary) and Calyciflorae (cup-shaped thalamus, inferior/half-inferior ovary) - Sub-class Gamopetalae (united petals) - split by ovary position/carpel number into Series Inferae, Heteromerae and Bicarpellatae - and Sub-class Monochlamydeae (incomplete flowers, apetalous or an undifferentiated perianth, sometimes both whorls absent). **Cl …