The plea of contractual arbitration (arbitrato irrituale) does not raise a question of jurisdiction but rather a question on the merits pertaining to the admissibility of the claim; it follows that the decision by which the court, upholding such plea, declares the claim inadmissible, is in the nature of a judgment dismissing the claim on the merits and not a ruling declining jurisdiction, so that an application for the determination of jurisdiction does not lie against it.