proviso quod

…if the plaintife or demandaunt desist in prosecuting an action, by bringing it to a triall, the defendant or tenent may take out the venire facias to the Shyreeue: which hath in it these words, Prouiso quod, &c. to this ende, that if the plaintife take out any writ to that purpose, the shyreeue shall summon but one Iurie vpon them both.