City cancelled twenty-three building permits it previously issued to plaintiffs, doing business as Gilbert E. Kinder Company, and the trial court commanded their re-issuance and validation. City has abandoned all its defenses except that it claims that the trial court erred in overruling its plea in abatement. City stipulated that all the allegations of fact in plaintiffs’ petition were true.

City’s plea in abatement was an unsworn plea that plaintiffs did not sue the City’s agent, the Director of Housing, who *480actually 'cancelled the permits. Defects of parties, plaintiff or defendant, should he raised by sworn pleading. Rule 93, Texas Rules of Civil Procedure. On appeal, City changed the direction of its plea in abatement and here argues that the cancellation was done by its Director of Housing and that this was ultra vires. This plea is presented for the first time on appeal, and we will disregard it. Pollock Paper & Box Co. v. East Texas Motor Freight Lines, Inc., 145 Tex. 634, 201 S.W.2d 228. Moreover, by its stipulation that the facts are true, City positively agreed that “City can-celled all of the permits.”

The judgment is affirmed.