Abstract During the first week of adult life, the protein content of the spermatheca increases by about 45% but the carbohydrate content does not change significantly. Incorporation of radiolabelled leucine into protein is high in newly emerged females but by day 1 has declined to about two-thirds the initial level, where it then remains. With SDS-PAGE about 30 protein bands separate, including six glycoprotein fractions. All bands are present throughout sexual maturation and except for one (at 25 Kd), show little change in quantity during this period. Allatectomy or hormone replacement therapy has little effect on the parameters measured and it is concluded that the development of secretory activity in the spermatheca is not controlled by juvenile hormone.