§ 81. Titles and head notes. If the title of any article or other division of a statute, or the head note of a section shall be amended or repealed in the body of the statute, or if a new article or other division having a title, or a new section having a new head note be added to a statute, the corresponding title or head note, if any, in an abstract of contents at the beginning of the statute, article or other division of the statute shall be deemed to be correspondingly amended or repealed, although there be no express reference thereto.