The municipal clerk shall examine the petition, within ten days of the date of its being filed with him, to ascertain whether or not it conforms to the requirements of this chapter. In examining the signatures of the electors he may, if in doubt as to the genuineness of any of them, compare them with the signatures contained in the registry books used at the last preceding general election. The petition shall be accepted if it substantially conforms to the form provided herein, the form being for the guidance of the parties and no petition shall be rejected by the clerk for any typographical deviation from the form provided herein or for any minor departure therefrom.