Where complaint alleged that defendants agreed with plaintiff, in consideration of his performing services, to give him exclusive right to secure an option for a lease on defendants' mining property, and that if lease should be taken, he should receive whatever he obtained above a royalty of thirty cents per ton, and that if defendants should themselves option the property it should not affect plaintiff's right to compensation, the failure to prove that plaintiff was the procuring cause of the lease was not a fatal variance. McRae v. Feigh, 173 N. W. 655, - Minn. Sup. - .