Abstract
The independent and joint effects of lowered oxygen tensions and increased carbon dioxide tensions on the adult and immature stages of Calandra oryzae L. (small strain) have been examined. The concentrations of the two gases that occurred among infested grain stored in air-tight containers have been measured. It is concluded that the death of the insects was due to the depletion of oxygen and that the associated accumulation of carbon dioxide played only a minor role. The young immature stages were the most susceptible to the changing concentrations of oxygen and carbon dioxide.