18304 ACHE CY Project I# Basic studies on the effect of I-rays upon“fish‘in various stages of development. Sections I and II# The eggs obtained from the five (5) year old chinock salmon female, marked A, and R., of the "gontrol® stockcontime to develop Sie atithe Samish Hatchery, State of Washington Department of Fisheries. As goon as these eggs develop to the "eyed" stage they will be transfered to the Applied Fisheries Laboratory, University of Washington, to contime their development. A very critical study will be made of the young fish produced to add to our knowledge of the variations expected in "control" but possibly inbred stock, Section XI Rainbow trout yearlings, females and males, from University of Washington stock were exposed to 50, 100, 500, 750, 1000, 1500 and/or 2500 r, A total of 128 yearling (nearly two yeara old) were irradiated in January 1945. An additional 20 fish were used as controls, The effect on the offspring of this stock to the exposure to X-rays prior to their first spawning (Spring of 1945) was described in the report "Some effects on embryos and young rainbow trout (Salmo gairdnerii Richardson) from exposing the parent fish to X-rays" UWFL-10, 2 “Project and sectionmmbers refer to the Project Chronology Chart and Summary OrFL93 revised March dl, 1948.