You need to determine where exactly the fluid is leaking . Did you change your fluid recently?
There are too many possibilities.
1. Rear seal
2. Pan Gasket
3. Rear solenoid
4. Aux pump
5. Governor cover
6. Breather cap (only if overfilled with fluid)
It could be one of these if coming from rear.
Check for correct fluid level. Jack up car start and check for leeks.