Section 38. No store or retail food store pharmacy department or retail store pharmacy department shall be kept open for the transaction of the retail drug business, or be advertised or represented as transacting such business, by means of any sign or advertisement containing the words ''drug store'', ''pharmacy'', ''apothecary'', ''drug'', ''drugs'', ''medicine shop'', or any combination of such words, or otherwise, unless it is registered with, and a permit therefor has been issued by the board as provided in the following section; provided, however, that said words, or any of them, may, with the written permission of the board, be used with respect to a store or retail food store pharmacy department or retail store pharmacy department not registered with, and not having a permit issued by, the board as aforesaid, if in the town, or voting precinct thereof, where such store or retail food store pharmacy department or retail store pharmacy department is located there is no store or retail food store pharmacy department or retail store pharmacy department so registered and having such a permit. Such permit shall be displayed in a conspicuous place in the store or retail food store pharmacy department or retail store pharmacy department for which it is issued. The word ''town'', as used in this section, shall not include city. Identification of a retail food store pharmacy department or retail store pharmacy department by use of the words ''drug store'', ''pharmacy'', ''apothecary'', ''drug'', ''drugs'', ''medicine shop'', or any combination thereof shall be restricted to the area registered by the board for the transaction of the retail drug business.