An active Reduction of Water Level in Insect Cuticle

Abstract
The water in cuticles excised from living cockroaches and locusts is not in osmotic equilibrium with their blood. It represents on average an osmotic pressure 15 atmospheres greater than the blood osmotic pressure. In the locust a cuticle in equilibrium with the blood would contain 60% more water. This is cited as evidence for the continuous expenditure of energy by the epidermal cell in regulating the water balance of the cuticle.