Where uncertainty exists as to the boundaries of any district shown upon the official zoning map, the following rules shall apply:

1.

Where district boundaries are indicated as following street, alley or lot lines, said lines shall be construed to be such boundaries.

2.

Where any public street or alley is hereafter officially vacated or abandoned, the regulations applicable to each parcel of abutting land shall apply to the portion of such street or alley added thereby by virtue of said vacation or abandonment.

3.

Territory which may hereafter be annexed to the City of South Bay shall be classified in the R-1 Single Family Dwelling District until otherwise changed by ordinance as provided herein; or unless the commission, after public hearing, shall otherwise provide.