1. Almagor, M., Bar-Tana, J. and Ron, A. 1977. J. Cell Biol. 75, 78a.
2. Berg, H. C. and Brown, D. A. 1972. Nature 239, 500.
3. Diehn, B., Feinlieb, M., Haupt, W., Hildebrand, E., Lenci, F. and Nultsch, W. 1977. Photochem. Photobiol. 26, 559.
4. Eckert, R. 1972. Science 176, 473.
5. Faure-Fremiet, E. 1967. In “Chemical Zoology” (G. W. Kidder, Ed.), Vol. I, 21. Academic Press, New York.