Radiation insult is immediate, but the cytological evidence for this insult may not follow for hours or days, depending, in part at least, upon the activity of the particular tissue under study. Histological and cytological analyses of exposed tissues days after exposure have not revealed the immediate disruptive and the subsequent reparative processes that occur. This study of the very early, and consequently radiosensitive, embryonic eye is made to bring out the sequence of responses to graded exposures of x-radiation. It reveals the remarkable powers of repair present in the embryo.
MATERIALS AND METHOD
CF1 female mice were time-mated with males of the same strain and 12.5 days later were exposed to whole-body x-radiations. Irradiation was achieved by a Quandrocondex constant-potential therapy machine run at 210 kvp and 15 ma., and the rays were selectively hardened by filtration with 0.28 mm. Cu and 0.50 mm. Al. The distance to the