When the defendant has been duly cited by publication in accordance with the preceding rule, and no appearance is entered within the time prescribed for pleadings, the court shall appoint an attorney to defend in behalf of such owner or owners, and proceed as in other causes where service is made by publication. It shall be the special duty of the court in all cases to see that its decree protects the rights of the unknown parties thereto. The judge of the court shall fix the fee of the attorney so appointed, which shall be entered and collected as costs against said unknown owner or owners.