Section 1E. The members of the board shall meet in the commonwealth, within thirty days after their appointment, and once a month thereafter at such times and places in the commonwealth as they may from time to time determine. They shall at least annually choose a chairman and a secretary from among their members, and shall make the appointments required to be made by them in the manner herein provided. Four board members shall constitute a quorum for the transaction of business, except in the case of the appointment or removal of the director of the division or the approval of the appointment or removal of the superintendent of the bureau of wildlife research and management as hereinafter provided for.
No appointment or removal of any person as director or superintendent shall be valid unless written notice of the meeting for such appointment or removal or approval thereof, setting forth the business to be transacted thereat, shall have been sent by registered mail, to each board member, at least twenty-one days prior to such meeting, and then only by the affirmative vote of three or more members present and voting.