Section 16(1)(a) in The Bihar And West Bengal (Transfer Of Territories) Act, 1956
(a)to determine on the basis of the population figures notified under section 15 the number of seats to be reserved for the Scheduled Castes and the Scheduled Tribes of Bihar and of West Bengal in the House of the People and in the Legislative Assembly of each of those States, having regard to the relevant provisions of the Constitution and of this Act; and