Opinion by

This is an action brought in the district court of Mayes county by the defendant in error, plaintiff below, against the plaintiffs in error, defendants below, for the specific performance of a contract for the sale of real estate. The parties will be referred to as they appeared in the trial court.

The petition of the plaintiff contains two causes of action; the first involves a 40-aere tract of land, and the second cause of action involves a 30-acre tract of land. The defendants file their answer, joining issues on both causes of action. The case was tried to the court and judgment was rendered for the plaintiff on the first cause of action, and for the defendants on the second cause of action. Both sides have appealed, each seeking to have the judgment rendered against him in the lower court reversed.

The plaintiff has set out his assignments of error by a cross-petition in error, in which he asks that the judgment of the lower court as to the second cause of action, involving the 30-acre tract, be reversed: but he has not filed a brief in support thereof as required by the rules of this court, nor offered any excuse for not doing so; and under the uniform holding of this court, the plaintiff will be deemed to have abandoned bis cross-petition in error and his appeal from the judgment of the lower court as to the second cause of action should be dismissed. Iralson v. Stang et al., 18 Okla. 423, 90 Pac. 446; Mann v. Oklahoma City Planing Mill & Box Mfg. Co., 48 Okla. 551, 150 Pac. 460; Woodward v. Bruhwilder, 54 Okla. 131, 153 Pac. 863; Simmons v. State, 54 Okla. 407, 153 Pac. 1159.

The defendant Coats is a tenant on a portion of this land, and is not a necessary-party here to a disposition of this case.

The record shows that the defendant Graham has filed his brief in support of the assignments of error set out by him in his petition in error, in which he seeks to have the action of the lower court reversed in rendering judgment for the plaintiff on the first cause of action, involving the 40-acre tract of land. The plaintiff has failed to file his brief in answer thereto, and has not offered any excuse for not doing so. The brief filed by the defendant appears to reasonably sustain the assignments of error of the defendant, and this court is not required to search the record to find some theory upon which the judgment below may be sustained. Incorporated Town of Kusa v. Bouggous, 82 Okla. 204, 200 Pac. 154; Russell & Washington v. Robertson, 82 Okla. 283, 200 Pac. 150; Obialero v. Henryetta Spelter Co., 82 Okla. 274, 200 Pac. 143; Walker v. Robinson, 66 Okla. 56, 166 Pac. 1042; Miles v. Bird, 41 Okla. 428, 138 Pac. 789; Butler et al. v. McSpadden, 25 Okla. 465, 107 Pac. 170.

Therefore, the cross-petition in error and the appeal of the plaintiff on the second cause of action are dismissed; and-the judgment of the lower court on the first cause of action is reversed and remanded, with directions to grant a new trial as to said first cause of action.

By the Court: It is so ordered.