Water Relations in An Insect, Thermobia Domestica

Abstract

1. The concentrations of Na⁺ and K⁺ in the haemolymph remain relatively constant during the moulting cycle. 2. Desiccation, desiccation followed by rehydration and starvation exert little or no effect on the concentrations of Na⁺ and K⁺ in the haemolymph. 3. The volume of haemolymph decreases during desiccation and increases after rehydration. 4. More Na⁺ is voided in the excreta during desiccation. 5. Repeated desiccation and rehydration causes the loss of both Na⁺ and K⁺ from the body. 6. The effects of desiccation and rehydration on the concentrations of chlorides and free amino acids in the haemolymph are described.