Coordination of control was first effected in the Sundarbans by the appointment of a Commissioner with all the duties, power and authority of a Collector of Land Revenue under the provisions of Regulation IX of 1816, the Commissionership was in existence in 1870, though the duties of the office had been considerably restricted. The unity implied that the same rules and practice were applied to all parts of the Sundarbans, however different in character. In addition to the lack of homogeneity between different tracts of the Sundarbans, the position was complicated by the different forms of leases and settlements in vogue over the whole area. It has already been stated that in 1846 permanently-settled tracts were excluded from the control of the Sundarban Commissioner.