When it appears from the pleadings that one or more defendants claim to be seized of the whole of a specific parcel of the premises of which partition is prayed, there may first be a separate trial of that question only, at the discretion of the presiding justice. When it appears on trial that any defendant has no interest in the estate, he shall be heard no further and the plaintiff shall recover of him the costs of the trial.
14 M.R.S. § 6507