|1. It is a prostrate, thickened underground stem
2. It is usually branched and rarely unbranched.
3. It is elongated in shape.
4. It contains a less amount of food material.
5. They are generally perennial and live for several years.
6. Growth is continuous so that succession of rhizome is not produced.
7. Examples ginger, water lily,
|1. This is a stout, solid, fleshy underground stem growing vertically.
2. It is usually unbranched.
3. It is spherical in shape.
4. It contains a heavy deposit of food material
5. They can leave only for few (1-3) years.
6. New corm is produced every year in the above or on the side of old corm.
7. Examples: Colocasia, Crocus.