Suits for specific performance.

42. Suits for specific performance.- In a suit for specific performance, whether with or without possession, fee shall be payable- (a) in the case of a contract of sale, computed on the amount of the consideration; (b) in the case of a contract of mortgage, computed on the amount agrees to be secured by the mortgage; (c) in the case of a contract of lease, computed on the aggregate amount of the fine or premium if any, and of the average of the annual rent agreed to be paid; (d) in the case of a contract of exchange, computed on the amount of the consideration, or as the case may be on the market value of the property, sought to be got in exchange; (e) in other cases, where the consideration for the promise sought to be enforced has a market value computed on such market value, or where such consideration has no market value at the rates specified in section 50.