The wall of alimentary canal (A.C) including small and large intestines possesses 4 layers:
Rugae − irregular folds formed by mucosa in stomach
Villi − These are finger-like folding formed by mucosa in small intestine. Cells that line villi bear microscopic projections called microvilli. These increase the surface area.
Villi have a network of capillaries and lacteal (a large lymph vessel). This helps in absorption of food in small intestine.