Eggs of Melanoplus differentialis were irradiated with dosages of 1,000-10,000 roentgens, in steps of 1,000 on each of the first six days after laying. Gross and microscopical studies of the eggs were made after the controls had reached diapause. It was found that the radiation on the first and second days had prevented subsequent development of all cells. Irradiation after the second day inhibited the development only of the cells of the embryo proper. It is therefore indicated that the yolk and serosa cells undergo 1:1 marked increase in their resistance to X-rays after the second day. The yolk and serosa cells are apparently able to complete the process of differentiation following exposure to the radiation. The most evident morphological expression of this differentiation is a marked increase in size, especially of the nucleus. In some of the eggs irradiated on the second day this process of differentiation was so affected that large masses of nuclear material were produced.
Proceedings of the Iowa Academy of Science
©1941 Iowa Academy of Science, Inc.
Slaughter, J. C.; Evans, T. C.; and Goodrich, J. P.
"Changes in Susceptibility to X-Rays of Certain Embryonic Cells of the Grasshopper (Abstract),"
Proceedings of the Iowa Academy of Science, 48(1), 482-483.
Available at: https://scholarworks.uni.edu/pias/vol48/iss1/124