Tests carried out in silo bins with phostoxin tablets and pellets at dosages of 3, 5, and 7 (and in exceptional cases 9) tablets per ton have shown that good results can also be obtained at lower dosages in case the exposure time would be prolonged to 7 resp. 10 days. Test insects were placed in test cages inside the grain and for comparison also infested grain was examined. In some cases also a dosage of 2 tablets/ton of grain gave satisfactory results. It was found that a dosage of 5 to 6 pellets per ton of grain at 7 days exposure time will be sufficient to kill all stages of development of the rice weevil; same results were obtained at 7 pellets per ton of grain at an exposure time of 6 days.