The numbers of sealed drone cells produced in seven honey bee colonies were counted at intervals throughout the period of their production. On the same days measurements were made of the amounts of total brood in these colonies, and the spread of the two sets of curves was compared. It is shown that the period when there was considerable drone brood present had only about half the duration of the corresponding period for total brood. The number of scaled drone cells in individual colonies differed considerably and was apparently not related to the formation of queen cells in preparation for swarming. In the five colonies which made swarm preparations the interval of time between the start of the large scale production of drone cells and the laying of the first eggs in queen cells was subject to rather wide variation, but had a mean duration of about 3 weeks.