Long term effects in survivors: The life spen, tumor incidence and catarect induction will be stidied in surviving mice exposed both to neutrons end gemna OQ reys. These enimels will be sent Db air to Furth at Cesk Ridge f-r observation. Gamma ray Survivors: There will be about 200 enimels at 2ach of the 29 ganye ray stations earnearsed for long term survival Studies. Following the shot, they will be pooled in grouvs of four (covering a dose range of 100 roentgens). Not more then 4200 animals will be returned to the states. They will be accompanied by controls (? how many) which will be given equivalent doses of 250 k.v. x-rays (for each individual group, not the pooled groups of four) according to the mouse dosimetry nessure- ments (My ovm oninion is that since noase dosimetry is @ rather new tool for celi- bration of radiation they should also have control a@ninals given doses based on the -hysical measurements of what the enimels received. “his would alley possible controversy in the future as to the signif- icence of the results.) The difference in life sosan, tunor incidence and caterect development between the animals exnosed in the field end those given ecuivalent doses f 250 k.v. x-reys will be studied. < Ge Only 200 non-irradisted controls will eclompany the expesed animels. The statisticians felt that no more were necessary since the differences in long tern effects between mo een oy