The process of oösorption is described. Leucine amino peptidase and esterase produced by the follicle cells remove the chorion and vitelline membrane. The oölemma grows into the oöcyte and islands of degeneration are formed. The follicle is the entity of oösorption and is isolated from adjoining follicles.

Under conditions of host deprivation oösorption begins earlier in older individuals than younger ones whose fat body is still large before egg production reaches its peak. The time of onset may be correlated with the reduction in the size of the fat body following the peak of egg production. This suggestion is supported by the reduced longevity of starved older individuals compared with younger ones.

Age has no effect on the rate of oösorption.