UK Parliament — House of Commons

the Committee of Selection shall nominate not fewer than sixteen nor more than fifty Members to serve on each general committee for the consideration of each bill allocated or referred to it, or for the consideration of instruments (whether or not in draft) referred to it.

That each of the said Standing Committees do consist of not less than Sixty, nor more than Eighty Members, to be nominated by the Committee of Selection, who shall have regard to the classes of Bills committed to such Committees, to the composition of The House, and to the qualifications of the Members selected; and shall have power to discharge Members from time to time, and to appoint others in substitution for those discharged. The Committee of Selection shall also have power to add not more than Fifteen Members to a Standing Committee in respect of any Bill referred to it, to serve on the Committee during the consideration of such Bill.