Section 72. The president

The president of the Seneca nation shall preside
  over the deliberations of the council and shall have only a casting vote
  therein.  He  shall from time to time give to the council information of
  the state of the nation, and recommend such measures as he  shall  judge
  necessary and expedient; and shall take care that the laws applicable to
  the  nation  be  faithfully executed. He shall have power to convene the
  council in extra session as often as, in his judgment, the interests  of
  the  nation  require,  and  to fill all vacancies that may occur therein
  until such vacancy  be  filled  by  election.  In  the  absence  of  the
  president,  the  council  shall  choose  from  among  their own number a
  presiding officer, pro tempore.