Raphide are needle shaped crystals of Calcium oxalate.
- Found in Pistia, Colacasia etc. in their petiole
- Calcium carbonate crystals found in the leaves of Ficus
- Also found in members of the families of Acanthaceae, Curcurbitaceae .
- In Ficus leaves, these crystals are arranged in the form of bunch of grapes.
- In Momordica, double cystoliths are found in the epidermal cells.
- Cystolith are formed in specialized cells called lithocysts in leaves.