This petitions is by the Madhya Pradesh Pan Merchants Association, Nagpur, though its Secretary L. B. Borgaonkar. Respondents 2 and 3, who are the Sales Tax Officer and the Assistant Sales Tax Officer respectively in the Nagpur district, have issued notices to the dealers forming the Association to submit returns of their sales of betel leaves with a view to assessing them to sales tax. The petitioner claims exemption from the operation of the Sales Tax Act, 1947, and seeks a writ or writs to restrain the respondents from charging sales tax on the sale of betel leaves. In the alternative, it urges that Act XVI of 1949 by which the exemption is withdrawn is ultra vires and illegal.

2. To understand the contention it is necessary to give a short history of the legislation on the subject. In Act XXI of 1947 exemption from the tax is granted by section 6 of the Act. This section reads as follows :-

"(1) No tax shall be payable under this Act on the sale of goods specified in the second column of Schedule II, subject to the conditions and exceptions, if any, set out in the corresponding entry in the third column thereof.

(2) The State Government may, after giving by notification n