The Influence of Temperature and Moisture on the Uptake and Loss of Water in the Eggs of Gryllulus Commodus Walker (Orthoptera—Gryllidae)

Abstract

1. Eggs placed on moist plaster took up water slowly at first and then more rapidly until they had reached their maximum water content. The duration of the initial period of slow water uptake was dependent upon temperature, becoming shorter as the temperature was raised. Similarly the duration of the period of rapid water uptake decreased with temperature. 2. No special water-absorbing structure was identified in the eggs of Gryllulus. 3. The rate of water loss from newly laid eggs was more rapid at higher than at lower temperatures under conditions of constant atmospheric saturation deficiency. 4. Newly laid eggs died if they lost more than about 20% of their original weight. 5. At 90% relative humidity, eggs which had completed water uptake lost water at a higher rate at high than at lower temperatures. The rate of water loss was also dependent on the stage of development of the embryo. 6. Eggs that had completed diapause development at 13° C. and had completed water uptake were able to lose about 30% of their weight through desiccation without being killed, but many of those that lost more than about 20% of their weight failed to develop when replaced on moist plaster; it seemed as if they had entered a state resembling diapause.