What is called venation ? Describe its types.

$\rightarrow$ Venation : The arrangement of veins and the veinlets in the lamina of leaf is termed as venation.

$\rightarrow$ When the veinlets form a network, the venation is termed as reticulate. When the veins run parallel to each other within a lamina, the venation is termed as parallel.

$\rightarrow$ Leaves of dicotyledonous plants generally possess reticulate venation, while parallel venation is the characteristic of most monocotyledons.