Fecha de publicación: 07/06/1967 Fuente: WIPO "beekeeper" 1,071,281. Bee hives. A. HILEY. March 25, 1964 [March 26, 1963], No. 11801/63. Heading A1M. A control structure for positioning at the entrance to a hive and on the alighting board comprises a lower part 1 including a frame member 14 defining with the alighting board an exit 14a the size of which can be adjusted to allow free passage of all bees or of worker bees only, and a trapping chamber 30 which is reached via funnel shaped passages 52 ending in an outlet just large enough for the queen to pass through, exits for worker bees being provided in the trapping chamber. The size of exit 14a can be adjusted by means of a lever 62 pivoted at one side of the structure and movable to tilt the structure. A queen excluder screen 18, 20 and gauze weather screen 22 are provided. The trapping chamber 30 is removable and provided with a transparent cover.