It shall be unlawful for any person, firm or corporation, acting either as principal or agent to sell to any person, firm or corporation any fruit tree or fruit trees, plants or shrubs representing same to be thrifty or of a certain kind, variety or description and thereafter to deliver to such purchaser in filling such order and in completing such sale any fruit trees, plants or shrubs of a different kind, variety or description than the kind, variety or description of such fruit trees, plants or shrubs so ordered and sold.