A rectangular box (A), open at the top and made of Styrofoam(RTM) is provided with six screws (B) serving as spacers between the outer surface of the box (A) and the inner surface of the frame feeder, a vertical partition, respectively. Syrup is filled into the compartment beside the space accommodating the box (A) floating on top of the syrup moving into the second compartment through a gap at the bottom of the partition. The bees can individually remove syrup through holes (Z) provided in the bottom of the small box (A).