Permeability to Water of the Shell of the Egg of Locusta Migratoria Migratorioides, with Observations on the Egg of Teleogryllus Commodus

Abstract

1. Eggs of Locusta migratoria migratorioides were cut open at one end, the tissues were removed, and the empty egg shells were filled with water or with an osmotic solution. The open end was tied off to form a balloon. Balloons containing water were placed in osmotic solutions, and those containing a solution were immersed water. 2. Balloons were made from eggs 1 or 2 days old before water absorption had begun, from eggs during the course of rapid water absorption and from eggs which water absorption was complete. Diapausing and non-diapausing eggs were used. The hydropylar end of the egg was included in the balloons in half the observations. 3. All balloons containing solution gained water and all those containing water lost it. Shells from diapausing eggs were much less permeable than all other categories Little difference was observed between balloons whether the hydropylar end was present or not. 4. Eggs exposed to unsaturated air lost water rapidly, except those in diapause. 5. Balloons made with the shells of young eggs of Teleogryllus commodus were also permeable to water in both directions. 6. The results are discussed in the light of their contribution to an understanding of the control of the absorption of water in insect eggs.