78. That subordinate legislation cannot be questioned on the ground of violation of principles of natural justice on which administrative action may be questioned has been held by this Court in Tulsipur Sugar Co. Ltd. v. Notified Area Committee, Tulsipur [AIR 1980 SC 882], Rameshchandra Kachardas Porwal v. State of Maharashtra [(1981) 2 SCC 722 ] and in Bates v. Lord Hailsham of St. Marylebone [(1972) 1 WLR 1373)]. A distinction must be made between delegation of a legislative function in the case of which the question of reasonableness cannot be enquired into and the investment by statute to exercise particular discretionary powers. In the latter case the question may be considered on all grounds on which administrative action may be questioned, such as, non-application of mind, taking irrelevant matters into consideration, failure to take relevant matters into consideration, etc, etc. On the facts and circumstances of a case, a subordinate legislation may be struck down a arbitrary or contrary to statute if it fails to take into account very vital facts which either expressly or by necessary implication are required to be taken into consideration by the statute or, say, the Constitution. This can only be done on the ground that it does not conform to the statutory or constitutional requirements or that it offends Article 14 or Article 19(1)( a ) of the Constitution. It cannot, no doubt, be done merely on the ground that it is not reasonable or that it has not taken into account relevant circumstances which the Court considers relevant.