1. This group of appeals arises out of an order passed by the High Court of Kerala holding that the Kerala Buildings Tax Act" 19 of 1961 is ultra vires the Legislature in that it infringes the equality clause of the Constitution. The State of Kerala has appealed against the decision with special leave granted by this Court.

2. The material provisions of the Kerala 'Buildings Act, 1961, may be briefly set out. The Act extends to the whole of the State of Kerala: S.1(2), and shall be deemed to have come into force with effect from March 2,1961: S.1(3). An "assessee" is defined by S 2(b) as meaning a person by whom building tax or any other sum of money is payable under the Act and includes every person in respect of whom any proceeding under the Act has been taken for the assessment of building tax payable by him. S.2(d) defines "building" as meaning a house, out-house, garage or any other structure or part thereof whether of masonry, bricks, wood, metal, or other material, but does not include any portable shelter or any shed constructed principally of mud, bamboos, leaves, grass or thatch or a latrine which is not attached to the main structure. "Floorage" is defined by