Abstract
Prepupae and pupae are shown to lose weight more rapidly at low than at high humidities. This more rapid loss of weight is due to loss of water alone and not to loss of dry matter.The limits of temperature and humidity which each of the two stages can survive have been mapped out. If the metamorphic period as a whole is considered, it is likely that the limits of temperature and humidity for survival and development will be narrower than for each stage considered alone.