Section 92B. All meats, poultry and edible fish, except soft shell clams and oysters, shall be sold at retail only by weight and, except when sold in package form bearing a plain and conspicuous statement of quantity of contents as provided in section one hundred and eighty-one, such weight shall be determined at the time of sale. Whoever himself or by his servant or agent violates any provision of this section shall be punished by a fine of ten dollars or shall be subject to a civil citation as provided in section 29A of chapter 98.