The development of Braula requires from 63-67 days as reported by Dukov (1964) (Morse, Honey bee pests..etc.). Another reprot (Abd El-salaam , 1962) mentioned that Development of Braula takes only 16- 23 days. If Apistan works on Braula it will kill adults only. This is because eggs, larvae, and pupae are in the capping of the honey cells. Medhat Nasr, Ph.D. Research Scientist, Ontario Beekeepers Association Ontario, Canada