For a proper determination of the question, it is necessary to refer to section 25 a of the Act which at the relevant time stood as under: 25 A. (1) Where, at the time of making an assessment ll under section 23, it is claimed by or on behalf of any member (1) (1957) 27 (2) (3) (4) 508 of a Hindu family hitherto assessed as undivided that a partition has taken place among the members of such family, the Income tax Officer shall make such inquiry thereinto as he may think fit, and if he is satisfied that the joint family property has been partitioned among the various members or groups of members in definite portions, he shall record an order to that effect: Provided that no such order shall be recorded until notices of the inquiry have been served on all the members of the family (2) Where Such an order has been passed, or where any person has succeeded to a business, profession or vocation formerly carried on by a Hindu undivided family, whose joint family property has been partitioned on or after the last day on which it carried on such business.