| Home | | Pharmacognosy |

Chapter: Pharmacognosy and Phytochemistry : Study of Different Families

A British systematic botanist J. Hutchinson published his work, The Families of Flowering Plants in 1926 on dicotyle-dons and in 1934 on monocotyledons. Hutchinson made it clear that the plants with sepals and petals are more primitive than the plants without petals and sepals on the assumption that free parts are more primitive than fused ones.



Habit: These are annual herbs.


Leaves: The leaves are radical and cauline, simple, alternate, often lobed, or rarely pinnately compound.


Inflorescence: A raceme (corymbose towards the top).

Flowers: The flowers are regular and cruciform, bisexual and complete hypogynous.


Calyx: They are sepals, 2+2, which are free, and in two whorls.


Corolla: There are four petals, free, in one whorl. They alternate with the sepals. They are cruciform. Each petal has distinct limb and claw.


Androecium: There are six stamens in two whorls, two short, outer ones and four long, inner ones (tetradynamous).


Gynoecium: There are two syncarpous carpels. The ovary is superior, at first one-celled, but later two-celled owing to the development of a false septum. There are often many ovules in each cell, sometimes only two. They are anatropous or campylotropous. The placentation is parietal.


Fruit: The fruit is a long, narrow siliqua or a short, broad silicula.

Seeds: These are exalbuminous. The embryo is curved. The seeds remain attached to a wiry framework, called the replum, which surrounds the fruit.


Floral formula: H K2+2 C4 A2+4 G(2)


                                                          Floral diagram of cruciferae

Examples: Black mustard (Brassica nigra). Floral diagram of cruciferae

Contact Us, Privacy Policy, Terms and Compliant, DMCA Policy and Compliant

TH 2019 - 2024; Developed by Therithal info.