64. Scale of rent for different classes of tenants.-Subject to the provisions of section 63, a tenant shall be liable to pay rent in accordance with the following scale:-

(a) a hereditary or a non-occupancy tenant, other than a sub-tenant	one-fifth of the produce of his holding;
(b) an occupancy tenant	one-sixth of the produce of his holding;
(c) an exproprietary tenant	one-eighth of the produce of his holding:

Provided that if in any area bighori at customary rate is payable for any crop, a tenant may elect to pay such rate for such crop: Provided further that if a tenant grows cotton, or a crop in which cotton predominates, on more than one fourth of the irrigable area of his holding, the rent of such excess area shall be payable at double thebighori at customary rates.