The selectmen of the towns of West Haven and Milford may, from time to time as they deem expedient, prohibit the taking of long or soft-shell clams from such portions of the natural clam grounds of their respective towns as they shall from time to time designate, for a period not exceeding one year at a time. When said selectmen designate any place or places within their respective towns from which the taking of long or soft-shell clams is prohibited as aforesaid, the selectmen of the town of West Haven shall publish at least twice in some newspaper published in the city of New Haven, and the selectmen of the town of Milford shall publish at least twice in some newspaper published or having a circulation in the town of Milford, a notice describing the grounds upon which such prohibition is operative, and shall further describe the boundaries of such grounds by posting notices, signed by the selectmen of the town in which such grounds are situated, upon the shore adjacent to such grounds. No person shall take or have in his possession in either of said towns any long or soft-shell clams of less than one and one-half inches in length; and no person shall take any long or soft-shell clams from any grounds from which the taking of the same is prohibited as aforesaid, during the time of such prohibition. Any person who violates any provision of this section shall be fined not more than two hundred fifty dollars.