FIFTEEN FIGURRSPrevious studies (Hicks, '54a, ?58, Hicks, Brown. and D 'Amato, '57) have described the mechanisms of the malf ormations following 150-200 r in the earlier stages of development and have provided some data on effects of higher and lower doses. The present study describes the rnalformative patterns that result when rats are irradiated with 150-200 r on one of the days of gestation, 12 to 20, and sorrie of the mechanisms involved in their formation. Eft'ects on the retina and cerebellum will he briefly considered, but because these structures continue to he radiosensitive and subject to malformation well into neonatal life, they will be the subjects of further separate studies.

No abstract