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VARIOUS TYPES OF VENATION

The arrangement and distribution of veins and veinlets on the lamina of a leaf is called venation.

They are of three types:

1. Reticulate Venation:

When the veins are irregularly distributed to form a channel, it is known as Reticulate Venation.

It is the characteristic feature seen in dicots.

They are of two types:

  1. Unicostate or Pinnate Reticulate:
    Leaf having a single main mid-rib.
    Example: Hibiscus, Mango
  2. Multicostate or Palmate Reticulate:
    Having two or more mid-ribs arising from a single point.
    They are further divided as:
    1. Multicostate convergent:
      Many mid-ribs in a curved fashion from base of blade to its apex.
      Example: Zizyphus (Beri)
    2. Multicostate divergent:
      Many mid-ribs arise at the base of the leaf and then diverge from one another towards the margin.
      Example: Papaya, Cucurbita

2.  Parallel Venation:

Veins are parallel and do not form a network.

They are of two types:

  1. Unicostate or Pinnate parallel:
    Lamina has a single prominent midrib from which lateral veins arise which run towards the margin.
    Example: Canna, Banana
  2. Multicostate or Palmate parallel:
    Several leaves run parallel to each other.
    They are further divided as:
    1. Multicostate convergent:
      Principal veins appear from the base of the lamina and converge at the apex.
      Example: Bamboo
    2. Multicostate divergent:
      Main veins appear from the base of the lamina and converge at the apex.
      Example: Fan palm

3. Furcate Venation:

Dichotomously branched veins. Also known as forked venation.
Example: Nephrolepis (Fern)

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Thanks A Lot But,You should also attach diagram
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