a. Where two or more boundaries coincide, only the symbol representing the higher-ranking boundary is shown.
b. Boundaries which are approximate or indefinite are appropriately labeled.
c. In cases where a boundary follows a road, stream, or river, usually only every third unit of the symbol is shown. The intervening symbol units are omitted, except where the omission would create uncertainty as to the alinement of the boundary.
d. Terminology of boundaries in foreign areas varies; see the map legend for the correct terms.
e. The following contain the approved symbols for boundaries.
