Opinion by
Mr. Justice Cohen,Atlantic & Gulf Coast Stevedores, Inc. (Atlantic) filed corporation income tax returns for the years 1955 *443through 1961 with the Commonwealth of Pennsylvania denying any liability for tax on the ground that it was engaged exclusively in interstate and foreign commerce and was, therefore, exempt from taxation by the State. '.The Commonwealth’s tax officials rejected Atlantic’s contention and made settlements imposing tax for each year, duly notifying Atlantic. Atlantic ignored the notices and filed no petitions for resettlement.
On April 5, 1965, the settlements having become final, the Commonwealth filed a certificate of its lien for these taxes with the Prothonotary of the Court of Common Pleas of Philadelphia County; and on May 3, 1965, it had issued and served on Atlantic a scire facias sur lien. Atlantic answered by denying its liability for tax in the same way it had originally claimed to be constitutionally exempt.
Almost five months later the Commonwealth filed preliminary objections to Atlantic’s answer, raising questions of jurisdiction, venue and sufficiency of the defense, all of which challenged Atlantic’s right to raise a defense on the merits in its answer to the sci. fa. and the lower court’s power to consider any such defense.
The court below dismissed the objections solely because they were not timely filed, but it indicated that the Commonwealth could obtain a prompt ruling on the issues raised by the preliminary objections simply by filing a motion for judgment on the pleadings. The Commonwealth appealed to this Court under the Act of 1925, P. L. 23, which permits interlocutory appeals on questions of jurisdiction and argues (1) that it may raise a jurisdictional question at any time in proceeding and (2) that the lower court had no jurisdiction to review the merits of Atlantic’s defense.
The Commonwealth is both right and wrong. It has confused the jurisdiction of the court below to act on the sci. fa. proceedings — a jurisdiction which it surely has — with the taxpayer’s attempt to raise the merits *444of a tax claim in such proceedings when it has not pursued its statutory remedies under “The Fiscal Code”, Act of April 9, 1929, P. L. 313, §§1102-1101, as amended, 72 P.S. §§1102-1101, as amended, for contesting the tax. We have consistently ruled that this may not be done by a taxpayer. Commonwealth v. Hitzelberger, 419 Pa. 354, 214 A. 2d 223 (1965); Commonwealth v. Lentz, 353 Pa. 98, 44 A. 2d 291 (1915).
Here, the Commonwealth invoked the lower court’s jurisdiction by instituting sci. fa. proceedings. Atlantic attempted to defend by contesting the power of the Commonwealth to impose any tax upon it, not by claiming payment. This it could not do, and its defense was subject to dismissal as legally insufficient on preliminary objections by the Commonwealth. Commonwealth v. Lentz, supra. Nonetheless, the lower court chose not to sustain the preliminary objections because of their late filing. We question this action since the lack of susbtance to Atlantic’s position is clear and a motion for judgment on the pleadings would raise the identical question. Under these circumstances there seems little reason for requiring strict adherence to the 20 day time limit of Rule of Civil Procedure 1026. In fact, the lower court should have considered the preliminary objections filed by the Commonwealth to have been a motion for judgment on the pleadings and thereby disposed of the matter.
. However, as the matter presently stands, the only question before us is one of jurisdiction. Unlike Hitzelberger, where the taxpayer improperly attempted to confer jurisdiction on the lower court by filing a motion to strike the tax lien, the jurisdiction of the lower court was here properly invoked by the Commonwealth’s own actions. Having done so, it cannot deny this jurisdiction now but must proceed by the means suggested to achieve its ends.
*445The order overruling the Commonwealth’s objections to the jurisdiction of the court below is affirmed.
Order affirmed.