1. Ashburner, M., and Richards, G., in Proc. R. ent. Soc. Symp. Insect Dev., 1975 (edit. by Lawrence, P. A.) (Blackwell, Oxford, in the press).
2. Shaaya, E., and Karlson, P., Devl Biol., 11, 424–432 (1965).
3. Wyatt, G. R., in Biochemical Actions of Hormones, 2 (edit. by Litwack G.), 385–490 (Academic, New York and London, 1972).
4. Borst, D. W., Bollenbacher, W. E., O'Connor, J. D., King, D. S., and Fristrom, J., Devl Biol., 39, 308–316 (1974).
5. Hoffman, J. A., et al., in Colloque int. CNRS Invert. Endocr., Lille 1975 (in the press).